A264331 Number of (n+1)X(3+1) arrays of permutations of 0..n*4+3 with each element having directed index change -1,1 1,0 1,-1 or 0,-1.

1, 4, 11, 40, 133, 464, 1573, 5373, 18376, 62754, 214317, 732135, 2500884, 8542281, 29179002, 99670233, 340453584, 1162924217, 3972328112, 13568709449, 46348108164, 158316261005, 540777999819, 1847193977280, 6309660580860

Offset

1,2

Comments

Column 3 of A264336.

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 5*a(n-2) +17*a(n-3) +22*a(n-4) +5*a(n-5) -29*a(n-6) -44*a(n-7) -25*a(n-8) +11*a(n-9) +20*a(n-10) +11*a(n-11) -a(n-12) -2*a(n-13) -a(n-14)

Example

Some solutions for n=4
..1..4..5..6....1..2..5..6....1..4..3..6....1..4..3..6....1..4..3..6
..0..2..7..3....0..8..9..3....0..2..9.10....0..8..2.10....0..2..7.10
..9.12.13.14....4.10..7.14....5.12..7.14....5.12.13..7....9..5.11.14
..8.16.10.11...13.16.17.11....8.16.11.18....9.16.11.18....8.16.17.18
.17.18.19.15...12.18.19.15...17.13.19.15...17.14.19.15...12.13.19.15

Crossrefs

Cf. A264336.

Sequence in context: A149262 A149263 A149264 * A243760 A149265 A149266

Adjacent sequences: A264328 A264329 A264330 * A264332 A264333 A264334

Keyword

nonn

Author

R. H. Hardin, Nov 11 2015

Status

approved