A264537 Number of (4+1) X (n+1) arrays of permutations of 0..n*5+4 with each element having directed index change -2,-2 -1,0 0,1 or 1,0.

0, 19, 40, 166, 824, 3256, 15028, 64156, 275764, 1203956, 5186196, 22489732, 97426420, 421553284, 1826019284, 7905435556, 34229151412, 148217266564, 641745438100, 2778733096676, 12031672904052, 52095855239236

Offset

1,2

Links

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

Formula

Empirical: a(n) = 3*a(n-1) + 18*a(n-3) + 120*a(n-5) - 24*a(n-6) + 288*a(n-7) + 256*a(n-10) for n>11.

Empirical g.f.: x^2*(19 - 17*x + 46*x^2 - 16*x^3 + 64*x^4 - 8*x^5 - 104*x^6 + 256*x^7 - 256*x^8 + 768*x^9) / (1 - 3*x - 18*x^3 - 120*x^5 + 24*x^6 - 288*x^7 - 256*x^10). - Colin Barker, Jan 08 2019

Example

Some solutions for n=4:
.12..6.14..2..9....5.13..1..8..3...12..0.14..2..3...12..6..1..2..3
..0..1.19..3..4....0.11..2..7..4...10..1..6.13..4....0.11.19..7..4
..5.10..7..8.13...22..6.24.12..9....5.23..7..8..9....5.16.24..8..9
.20.11.22.17.24...10.21.16.23.14...20.11.22.17.24...10.21.22.13.14
.15.16.21.18.23...15.20.17.18.19...15.16.21.18.19...15.20.17.18.23

Crossrefs

Row 4 of A264534.

Sequence in context: A041718 A041720 A098850 * A164078 A128677 A065349

Adjacent sequences: A264534 A264535 A264536 * A264538 A264539 A264540

Keyword

nonn

Author

R. H. Hardin, Nov 17 2015

Status

approved