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Longest Pathology Puzzles By Size

Zachary DeStefano edited this page Nov 18, 2023 · 39 revisions

Longest Pathology Puzzles By Size

This wiki page documents the longest known PP1 and PP2 puzzles which fit within small $M \times N$ rectangles.

Outside of trivial cases, these numbers should be considered lower bounds for the longest possible puzzles of various sizes.

To preview and play any of these levels, just copy the level data into the Pathology Level Creator

PP1

In PP1, all boxes can be pushed from all sides and there are no holes.

We have the following results for small PP1 puzzles:

2 3 4 5 6 7 8 $\cdots$ N
1 1 2 3 4 5 6 7 $N - 1$
2 2 4 5 7 9 10 12 $\lfloor\frac{3N}{2}\rfloor$
3 8 11 14 17 20 23 $3 N - 1$
4 14 18 26 30 34 $4 (N + \lfloor\frac{N}{3}\rfloor) - 6$
5 34 40 46 54 ?
6 49 59 65 ?
7 67 78 ?
8 90 ?

The results for rectangular boards with at most 25 spaces have been confirmed optimal by mathmasterzach by exhaustive computer search.

$1 \times N$

Trivial construction of the form: 40...03

$2 \times 2$

40
03

$2 \times 3$

413
000

$2 \times 4$

4113
0000

$2 \times N$

For odd $N \geq 5$, the optimal is a zig-zag pattern.

41000
00013

For even $N > 5$, the optimal is a zig-zag pattern with a delaying block at the start.

041000
020003

$3 \times N$

A lock with a long handle.

00...020
41...123
00...020

$4 \times 4$

Two very different solutions, found by Flashback and dgriff24 respectively.

0410
0232
0220
0200
0314
2200
0020
2020

$4 \times 5$

Expanded version of dgriff24's $4 \times 4$

11130
00422
01200
00201

3 More designs by davidspencer6174

00010
41023
01120
00020
00410
00232
02220
00200
02010
42023
00120
10020

$4 \times 6$

By davidspencer6174

000130
010422
011200
000201

$4 \times 7$

Expanded version of davidspencer6174's $4 \times 6$

0000130
0110422
0111200
0000201

$4 \times 8$

Expanded version of davidspencer6174's $4 \times 6$

00000130
01110422
01111200
00000201

$4 \times N$

The best we know so far is a continuation of the above pattern with "wiggles": Ex.

000000100000130
011110001110422
010001110001200
000100000100201

$5 \times 5$

Hem's hemlock

02400
22220
02320
00100
10001

$5 \times 6$

By davidspencer6174

100000
001022
023200
022221
004101

$5 \times 7$

By davidspencer6174

0041000
0222210
0232010
0010100
1000000

$5 \times 8$

By davidspencer6174

02001000
12200010
42311110
02200010
00001000

$6 \times 6$

By Hem

100001
002200
022310
042200
122001
020011

$6 \times 7$

By Hem

1010001
1224200
0022220
2002320
0220100
1000001

$6 \times 8$

By Hem

10000111
00220011
02231001
04220200
12200220
02000020

$7 \times 7$

By Hem

1110020
0200220
1220200
0422020
0223100
0022001
1000011

$7 \times 8$

By Hem

0000110
0110022
0140220
0222200
0232000
0010220
1002022
1100000

$8 \times 8$

Hem's Boundary Unstable

02000020
12200220
10220200
00022001
01002200
01142310
00112200
10000001

PP2/Pathology

We have the following results for small PP2 puzzles:

2 3 4 5 6 7 8 $\cdots$ N
1 1 2 3 4 5 6 7 $N - 1$
2 2 4 6 10 16 19 24 $\Theta(N^2)$
3 10 16 32 49 82 91 $ >= N^2 + 3N - 17$
4 32 70 152 ? 189 ?
5 122 200 ? ? ?
6 300 ? ? ?
7 ? 386 ?
8 504? ?

$2 \times N$

The longest $2 \times 2$ and $2 \times 3$ match the results for PP1.

The longest $2 \times 4$, 5, and 6, were found by LifereaperX: LifereaperX's 2x4, LifereaperX's 2x5, LifereaperX's 2x6

sspenst provides a general construction for an $2 \times N$ with $N > 5$.

if $N = 0 \mod 3$ then we can achieve $\frac{N^2 + 2N}{3}$ steps

For $N = 6$ we have:

310000
552024

To scale this puzzle, insert $3 \times 2$ segments of the form:

000
520

Between the last hole and the first box, ex.

310000 -> 310000000 -> 310000000000
552024 -> 555202024 -> 555520202024

if $N = 1 \mod 3$ then we can achieve $\frac{N^2 + 2N - 6}{3}$

For $N = 7$ we have:

3100000
5502024

The construction is similar to that of $N = 0 \mod 3$, but now there is a space between the boxes and the holes

if $N = 2 \mod 3$ then we can achieve $\frac{N^2 + 2N - 14}{3}$

For $N = 8$ we have:

31020050
55042020

For $N = 11$ we have:

31020005000
55540202020

The construction following $N = 11$ is similar to those above.

$3 \times 3$

LifereaperX's 3x3

060
370
140

$3 \times 4$

LifereaperX's 3x4

0413
0210
0255

$3 \times 5$

By davidspencer6174 and mathmasterzach

08555
0BH29
04535

$3 \times 6$

By davidspencer6174

000085
0CBA01
004153

$3 \times 7$

davidspencer6174's Baker's Dozen

05020000
02BF0H41
0B5B1053

$3 \times 8$

davidspencer6174's Insular Gigantism

00C00005
022F0A0C
004G1053

$4 \times 4$

RisingStar111's 4x4

0600
5JD0
3A40
5080

$4 \times 5$

davidspencer6174's Beyond Measure

52020
0F4E3
CG625
585B5

$4 \times 6$

davidspencer6174's Break Infinity

000000
0E0I90
0F2G35
000465

$4 \times 8$

Reach's Yang-Mills Theory

50008565
59F000I4
53EH20F0
58000000

$5 \times 5$

davidspencer6174's Heaping Tablespoon

30200
51020
4I2F0
010F0
00000

$5 \times 6$

Neonesque's Breaking a Barrier

000005
01C245
020515
0BB715
000013

$6 \times 6$

kjs0722's R8

550060
02A7G0
0F4090
0EH000
001111
055553

$7 \times 8$

By qqwref

00013555
02001155
0C200145
00220105
02000100
02120050
10000000

$8 \times 8$

qqwref's Tiny Torment (possibly not fully optimized for step count)

00013555
0C201155
02000155
02220155
02000145
00222100
02100050
000000I0

Asymptotics

The best known asymptotic growth for PP1 levels on an $n \times n$ grid is $\Omega(n^4)$. In the top half of the grid, one can create $\Theta(n^2)$ directional locks in alternating directions in the style of the level Forgive Me. In the lower half of the grid, one can make a winding path of length $\Theta(n^2)$ that must be traversed once per directional lock.

The best known asymptotic growth for PP2 levels is exponential. One exponential construction is known: a modified version of Sokoban's exponential Fibo construction showcased by qqwref in Fibo.