A183658 Number of (n+1) X 6 0..5 arrays with every 2 X 2 subblock summing to 10.

87686, 204246, 563114, 1755246, 5992826, 21960366, 85187834, 346364046, 1465105466, 6410498286, 28882789754, 133518567246, 631437605306, 3047705625006, 14983976602874, 74921193336846, 380489261932346

Offset

1,1

Comments

Column 5 of A183662.

Links

R. H. Hardin, Table of n, a(n) for n = 1..29

Formula

Empirical: a(n) = 21*a(n-1) - 175*a(n-2) + 735*a(n-3) - 1624*a(n-4) + 1764*a(n-5) - 720*a(n-6).

Empirical g.f.: 2*x*(43843 - 818580*x + 5809499*x^2 - 19388154*x^3 + 29979432*x^4 - 16796160*x^5) / ((1 - x)*(1 - 2*x)*(1 - 3*x)*(1 - 4*x)*(1 - 5*x)*(1 - 6*x)). - Colin Barker, Apr 02 2018

Example

Some solutions for 3 X 6:
..3..3..1..2..3..1....0..3..4..1..1..0....1..5..2..4..0..4....0..4..1..5..2..5
..3..1..5..2..3..3....5..2..1..4..4..5....2..2..1..3..3..3....5..1..4..0..3..0
..4..2..2..1..4..0....0..3..4..1..1..0....4..2..5..1..3..1....0..4..1..5..2..5

Crossrefs

Cf. A183662.

Sequence in context: A253340 A232674 A236788 * A234442 A204508 A180106

Adjacent sequences: A183655 A183656 A183657 * A183659 A183660 A183661

Keyword

nonn

Author

R. H. Hardin, Jan 06 2011

Status

approved