A264281 Number of (n+1) X (4+1) arrays of permutations of 0..n*5+4 with each element having directed index change 0,0 0,1 1,0 or -1,-2.

16, 102, 675, 4484, 29742, 197283, 1308629, 8680430, 57579243, 381936079, 2533467942, 16805062848, 111471762753, 739417281750, 4904721187204, 32534119120513, 215806131795839, 1431490625216236, 9495399380127733

Offset

1,1

Links

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

Formula

Empirical: a(n) = 7*a(n-1) - 2*a(n-2) - 2*a(n-3) - 6*a(n-4) + a(n-5) + 3*a(n-6).

Empirical g.f.: x*(16 - 10*x - 7*x^2 - 5*x^3 + 4*x^4 + 3*x^5) / ((1 - x)*(1 - 6*x - 4*x^2 - 2*x^3 + 4*x^4 + 3*x^5)). - Colin Barker, Jan 07 2019

Example

Some solutions for n=4:
..7..1..9..2..4....0..1..2..3..4....0..8..1..2..4....0..1..2..3..4
..0..6.14..3..8...12.13..6..7..9...12..6..7..3..9....5..6.14..7..9
..5.10.11.12.13....5.18.11..8.14....5.10.11.13.14...10.11.12..8.13
.22.16.24.17.18...10.15.16.17.19...15.16.24.18.19...22.16.24.17.18
.15.20.21.23.19...20.21.22.23.24...20.21.17.22.23...15.20.21.23.19

Crossrefs

Column 4 of A264285.

Sequence in context: A224406 A223016 A253390 * A240257 A199773 A245872

Adjacent sequences: A264278 A264279 A264280 * A264282 A264283 A264284

Keyword

nonn

Author

R. H. Hardin, Nov 10 2015

Status

approved