A264470 Number of (n+1) X (n+1) arrays of permutations of 0..(n+1)^2-1 with each element having directed index change 0,1 1,0 2,1 or -1,-1.

0, 2, 6, 120, 3540, 310748, 74367790, 44706530288, 66581992940380, 252580385620049120

Offset

1,2

Comments

Diagonal of A264476.

Links

Table of n, a(n) for n=1..10.

Example

Some solutions for n=4
..6..0..8..9..3....6..0..1..2..3....6..7..1..9..3....6..0..8..9..3
.11..1..2.14..4...11..5.13.14..4....0..5..2.14..4...11..5..2..7..4
.16.10..7.19.13...16.17..7..8..9...16.17.11..8.13...16.10..1.12.13
.21..5.12.24.18...10.22.23.24.18...10.22.23.24.18...21.22.23.24.14
.15.20.17.22.23...15.20.21.12.19...15.20.21.12.19...15.20.17.18.19

Crossrefs

Cf. A264476.

Sequence in context: A212158 A058251 A180058 * A039716 A164955 A060001

Adjacent sequences: A264467 A264468 A264469 * A264471 A264472 A264473

Keyword

nonn

Author

R. H. Hardin, Nov 14 2015

Status

approved