A264529 Number of (n+1)X(3+1) arrays of permutations of 0..n*4+3 with each element having directed index change -2,-2 -1,0 0,1 or 1,0.

1, 2, 13, 40, 229, 696, 3273, 12832, 52897, 209890, 848673, 3410748, 13734005, 55435856, 222621989, 897990076, 3610748165, 14552830034, 58558270001, 235878435500, 949470694545, 3823609350504, 15393910820101, 61985526413732

Offset

1,2

Comments

Column 3 of A264534.

Links

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

Formula

Empirical: a(n) = 4*a(n-1) +13*a(n-2) -60*a(n-3) -42*a(n-4) +392*a(n-5) -102*a(n-6) -1668*a(n-7) +1431*a(n-8) +7740*a(n-9) -12835*a(n-10) -31952*a(n-11) +73992*a(n-12) +92400*a(n-13) -275368*a(n-14) -173104*a(n-15) +697118*a(n-16) +203576*a(n-17) -1254966*a(n-18) -135080*a(n-19) +1665556*a(n-20) -1665556*a(n-22) +135080*a(n-23) +1254966*a(n-24) -203576*a(n-25) -697118*a(n-26) +173104*a(n-27) +275368*a(n-28) -92400*a(n-29) -73992*a(n-30) +31952*a(n-31) +12835*a(n-32) -7740*a(n-33) -1431*a(n-34) +1668*a(n-35) +102*a(n-36) -392*a(n-37) +42*a(n-38) +60*a(n-39) -13*a(n-40) -4*a(n-41) +a(n-42)

Example

Some solutions for n=4
..4.11..6..2....4.11..1..2...10.11..6..7....4.11..6..2...10..0..6..2
..0..1..5..3....0..9..5..3....0..1..2..3....0..1..5..3....8..1..5..3
.18.13..9..7...18..8..6..7....4..5.14.15...18..8..9..7....4.19..9..7
..8.17.10.19...16.17.10.19....8..9.13.19...16.17.10.19...16.17.18.11
.12.16.14.15...12.13.14.15...12.16.17.18...12.13.14.15...12.13.14.15

Crossrefs

Cf. A264534.

Sequence in context: A216155 A011919 A323684 * A263979 A042795 A361071

Adjacent sequences: A264526 A264527 A264528 * A264530 A264531 A264532

Keyword

nonn

Author

R. H. Hardin, Nov 17 2015

Status

approved