diff --git a/.github/.keepalive b/.github/.keepalive
deleted file mode 100644
index 7bbee22b..00000000
--- a/.github/.keepalive
+++ /dev/null
@@ -1 +0,0 @@
-2024-10-01T02:47:28.812Z
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 344158a9..d5027f6b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -86,6 +86,28 @@
+
+
+#### [@stdlib/constants/float64/max-safe-nth-double-factorial](https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/constants/float64/max-safe-nth-double-factorial)
+
+
+
+
+
+##### Features
+
+- [`d0ebce3`](https://github.com/stdlib-js/stdlib/commit/d0ebce3a1ed53532f2bee61096fa08400f534437) - add `constants/float64/max-safe-nth-double-factorial` [(#2966)](https://github.com/stdlib-js/stdlib/pull/2966)
+
+
+
+
+
+
+
+
+
+
+
#### [@stdlib/constants/float64/num-high-word-significand-bits](https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/constants/float64/num-high-word-significand-bits)
@@ -131,6 +153,7 @@ A total of 2 people contributed to this release. Thank you to the following cont
+- [`d0ebce3`](https://github.com/stdlib-js/stdlib/commit/d0ebce3a1ed53532f2bee61096fa08400f534437) - **feat:** add `constants/float64/max-safe-nth-double-factorial` [(#2966)](https://github.com/stdlib-js/stdlib/pull/2966) _(by Gunj Joshi, Athan Reines)_
- [`e6b6ffb`](https://github.com/stdlib-js/stdlib/commit/e6b6ffbbc11a52fe64529527ceb6e0afc2df31d1) - **feat:** add `constants/float32/max-safe-fibonacci` [(#2904)](https://github.com/stdlib-js/stdlib/pull/2904) _(by Gunj Joshi)_
- [`51787c8`](https://github.com/stdlib-js/stdlib/commit/51787c84fc5805a0144c2596ad8ac631470458b5) - **feat:** add `constants/float64/num-high-word-significand-bits` [(#2889)](https://github.com/stdlib-js/stdlib/pull/2889) _(by Gunj Joshi, Athan Reines)_
- [`511ae22`](https://github.com/stdlib-js/stdlib/commit/511ae22019022653f58464a98034b1821d979714) - **fix:** update folder name [(#2871)](https://github.com/stdlib-js/stdlib/pull/2871) _(by Gunj Joshi)_
diff --git a/float64/max-safe-nth-double-factorial/README.md b/float64/max-safe-nth-double-factorial/README.md
new file mode 100644
index 00000000..cad03050
--- /dev/null
+++ b/float64/max-safe-nth-double-factorial/README.md
@@ -0,0 +1,166 @@
+
+
+# FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL
+
+> Maximum safe nth [double factorial][double-factorial] when stored in [double-precision floating-point][ieee754] format.
+
+
+
+## Usage
+
+
+
+```javascript
+var FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL = require( '@stdlib/constants/float64/max-safe-nth-double-factorial' );
+```
+
+#### FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL
+
+The maximum [safe][safe-integers] nth [double factorial][double-factorial] when stored in [double-precision floating-point][ieee754] format.
+
+
+
+```javascript
+var bool = ( FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL === 301 );
+// returns true
+```
+
+
+
+
+
+
+
+## Examples
+
+
+
+
+
+```javascript
+var FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL = require( '@stdlib/constants/float64/max-safe-nth-double-factorial' );
+
+function factorial( n ) {
+ var a;
+ var i;
+
+ a = 1;
+ for ( i = n; i >= 2; i -= 2 ) {
+ a *= i;
+ }
+ return a;
+}
+
+var v;
+var i;
+for ( i = 0; i < 400; i++ ) {
+ v = factorial( i );
+ if ( i > FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL ) {
+ console.log( 'Unsafe: %d', v );
+ } else {
+ console.log( 'Safe: %d', v );
+ }
+}
+```
+
+
+
+
+
+
+
+* * *
+
+
+
+## C APIs
+
+
+
+
+
+
+
+
+
+
+
+### Usage
+
+```c
+#include "stdlib/constants/float64/max_safe_nth_double_factorial.h"
+```
+
+#### STDLIB_CONSTANT_FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL
+
+Macro for the maximum [safe][safe-integers] nth [double factorial][double-factorial] when stored in [double-precision floating-point][ieee754] format.
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+[safe-integers]: http://www.2ality.com/2013/10/safe-integers.html
+
+[double-factorial]: https://en.wikipedia.org/wiki/Double_factorial
+
+[ieee754]: https://en.wikipedia.org/wiki/IEEE_754-1985
+
+
+
+
+
+
+
+
diff --git a/float64/max-safe-nth-double-factorial/docs/repl.txt b/float64/max-safe-nth-double-factorial/docs/repl.txt
new file mode 100644
index 00000000..fbde931d
--- /dev/null
+++ b/float64/max-safe-nth-double-factorial/docs/repl.txt
@@ -0,0 +1,13 @@
+
+{{alias}}
+ Maximum safe nth double factorial when stored in double-precision floating-
+ point format.
+
+ Examples
+ --------
+ > {{alias}}
+ 301
+
+ See Also
+ --------
+
diff --git a/float64/max-safe-nth-double-factorial/docs/types/index.d.ts b/float64/max-safe-nth-double-factorial/docs/types/index.d.ts
new file mode 100644
index 00000000..31003165
--- /dev/null
+++ b/float64/max-safe-nth-double-factorial/docs/types/index.d.ts
@@ -0,0 +1,33 @@
+/*
+* @license Apache-2.0
+*
+* Copyright (c) 2024 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+// TypeScript Version: 4.1
+
+/**
+* Maximum safe nth double factorial when stored in double-precision floating-point format.
+*
+* @example
+* var max = FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL;
+* // returns 301
+*/
+declare const FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL: number;
+
+
+// EXPORTS //
+
+export = FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL;
diff --git a/float64/max-safe-nth-double-factorial/docs/types/test.ts b/float64/max-safe-nth-double-factorial/docs/types/test.ts
new file mode 100644
index 00000000..becaf061
--- /dev/null
+++ b/float64/max-safe-nth-double-factorial/docs/types/test.ts
@@ -0,0 +1,28 @@
+/*
+* @license Apache-2.0
+*
+* Copyright (c) 2024 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+import FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL = require( './index' );
+
+
+// TESTS //
+
+// The export is a number...
+{
+ // eslint-disable-next-line @typescript-eslint/no-unused-expressions
+ FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL; // $ExpectType number
+}
diff --git a/float64/max-safe-nth-double-factorial/examples/index.js b/float64/max-safe-nth-double-factorial/examples/index.js
new file mode 100644
index 00000000..dc9d2bdf
--- /dev/null
+++ b/float64/max-safe-nth-double-factorial/examples/index.js
@@ -0,0 +1,43 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2024 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+var FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL = require( './../lib' ); // eslint-disable-line id-length
+
+function factorial( n ) {
+ var a;
+ var i;
+
+ a = 1;
+ for ( i = n; i >= 2; i -= 2 ) {
+ a *= i;
+ }
+ return a;
+}
+
+var v;
+var i;
+for ( i = 0; i < 400; i++ ) {
+ v = factorial( i );
+ if ( i > FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL ) {
+ console.log( 'Unsafe: %d', v );
+ } else {
+ console.log( 'Safe: %d', v );
+ }
+}
diff --git a/float64/max-safe-nth-double-factorial/include/stdlib/constants/float64/max_safe_nth_double_factorial.h b/float64/max-safe-nth-double-factorial/include/stdlib/constants/float64/max_safe_nth_double_factorial.h
new file mode 100644
index 00000000..922f522c
--- /dev/null
+++ b/float64/max-safe-nth-double-factorial/include/stdlib/constants/float64/max_safe_nth_double_factorial.h
@@ -0,0 +1,27 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2024 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+#ifndef STDLIB_CONSTANTS_FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL
+#define STDLIB_CONSTANTS_FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL
+
+/**
+* Macro for the maximum safe nth double factorial when stored in double-precision floating-point format.
+*/
+#define STDLIB_CONSTANT_FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL 301
+
+#endif // !STDLIB_CONSTANTS_FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL_H
diff --git a/float64/max-safe-nth-double-factorial/lib/index.js b/float64/max-safe-nth-double-factorial/lib/index.js
new file mode 100644
index 00000000..65a8a703
--- /dev/null
+++ b/float64/max-safe-nth-double-factorial/lib/index.js
@@ -0,0 +1,49 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2024 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+/**
+* Maximum safe nth double factorial when stored in double-precision floating-point format.
+*
+* @module @stdlib/constants/float64/max-safe-nth-double-factorial
+* @type {integer}
+*
+* @example
+* var FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL = require( '@stdlib/constants/float64/max-safe-nth-double-factorial' );
+* // returns 301
+*/
+
+
+// MAIN //
+
+/**
+* The maximum safe nth double factorial when stored in double-precision floating-point format.
+*
+* @constant
+* @type {integer}
+* @default 301
+* @see [double factorial]{@link https://en.wikipedia.org/wiki/Double_factorial}
+* @see [IEEE 754]{@link https://en.wikipedia.org/wiki/IEEE_754-1985}
+*/
+var FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL = 301|0; // eslint-disable-line id-length
+
+
+// EXPORTS //
+
+module.exports = FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL;
diff --git a/float64/max-safe-nth-double-factorial/manifest.json b/float64/max-safe-nth-double-factorial/manifest.json
new file mode 100644
index 00000000..844d692f
--- /dev/null
+++ b/float64/max-safe-nth-double-factorial/manifest.json
@@ -0,0 +1,36 @@
+{
+ "options": {},
+ "fields": [
+ {
+ "field": "src",
+ "resolve": true,
+ "relative": true
+ },
+ {
+ "field": "include",
+ "resolve": true,
+ "relative": true
+ },
+ {
+ "field": "libraries",
+ "resolve": false,
+ "relative": false
+ },
+ {
+ "field": "libpath",
+ "resolve": true,
+ "relative": false
+ }
+ ],
+ "confs": [
+ {
+ "src": [],
+ "include": [
+ "./include"
+ ],
+ "libraries": [],
+ "libpath": [],
+ "dependencies": []
+ }
+ ]
+}
diff --git a/float64/max-safe-nth-double-factorial/package.json b/float64/max-safe-nth-double-factorial/package.json
new file mode 100644
index 00000000..5d3a1f59
--- /dev/null
+++ b/float64/max-safe-nth-double-factorial/package.json
@@ -0,0 +1,72 @@
+{
+ "name": "@stdlib/constants/float64/max-safe-nth-double-factorial",
+ "version": "0.0.0",
+ "description": "Maximum safe nth double factorial when stored in double-precision floating-point format.",
+ "license": "Apache-2.0",
+ "author": {
+ "name": "The Stdlib Authors",
+ "url": "https://github.com/stdlib-js/stdlib/graphs/contributors"
+ },
+ "contributors": [
+ {
+ "name": "The Stdlib Authors",
+ "url": "https://github.com/stdlib-js/stdlib/graphs/contributors"
+ }
+ ],
+ "main": "./lib",
+ "directories": {
+ "doc": "./docs",
+ "example": "./examples",
+ "include": "./include",
+ "lib": "./lib",
+ "test": "./test"
+ },
+ "types": "./docs/types",
+ "scripts": {},
+ "homepage": "https://github.com/stdlib-js/stdlib",
+ "repository": {
+ "type": "git",
+ "url": "git://github.com/stdlib-js/stdlib.git"
+ },
+ "bugs": {
+ "url": "https://github.com/stdlib-js/stdlib/issues"
+ },
+ "dependencies": {},
+ "devDependencies": {},
+ "engines": {
+ "node": ">=0.10.0",
+ "npm": ">2.7.0"
+ },
+ "os": [
+ "aix",
+ "darwin",
+ "freebsd",
+ "linux",
+ "macos",
+ "openbsd",
+ "sunos",
+ "win32",
+ "windows"
+ ],
+ "keywords": [
+ "stdlib",
+ "stdmath",
+ "constant",
+ "const",
+ "max",
+ "maximum",
+ "factorial",
+ "number",
+ "safe",
+ "integer",
+ "double",
+ "dbl",
+ "floating",
+ "point",
+ "floating-point",
+ "float",
+ "float64",
+ "f64",
+ "ieee754"
+ ]
+}
diff --git a/float64/max-safe-nth-double-factorial/test/test.js b/float64/max-safe-nth-double-factorial/test/test.js
new file mode 100644
index 00000000..f7a7b910
--- /dev/null
+++ b/float64/max-safe-nth-double-factorial/test/test.js
@@ -0,0 +1,38 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2024 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var tape = require( 'tape' );
+var FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL = require( './../lib' ); // eslint-disable-line id-length
+
+
+// TESTS //
+
+tape( 'main export is a number', function test( t ) {
+ t.ok( true, __filename );
+ t.strictEqual( typeof FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL, 'number', 'main export is a number' );
+ t.end();
+});
+
+tape( 'the exported value is 301', function test( t ) {
+ t.strictEqual( FLOAT64_MAX_SAFE_NTH_DOUBLE_FACTORIAL, 301, 'returns expected value' );
+ t.end();
+});