A183677 Number of (n+1) X 5 0..7 arrays with every 2 X 2 subblock summing to 14.

90784, 316232, 1287136, 5836328, 28648864, 149494472, 819074656, 4670563688, 27537504544, 167042421512, 1038458116576, 6595836942248, 42695895281824, 281093606593352, 1879017187820896, 12735396730476008, 87413674868252704

Offset

1,1

Comments

Column 4 of A183680.

Links

R. H. Hardin, Table of n, a(n) for n = 1..32

Formula

Empirical: a(n) = 36*a(n-1) - 546*a(n-2) + 4536*a(n-3) - 22449*a(n-4) + 67284*a(n-5) - 118124*a(n-6) + 109584*a(n-7) - 40320*a(n-8).

Empirical g.f.: 8*x*(11348 - 368999*x + 4933856*x^2 - 34954265*x^3 + 140612372*x^4 - 317862116*x^5 + 368412624*x^6 - 165150720*x^7) / ((1 - x)*(1 - 2*x)*(1 - 3*x)*(1 - 4*x)*(1 - 5*x)*(1 - 6*x)*(1 - 7*x)*(1 - 8*x)). - Colin Barker, Apr 04 2018

Example

Some solutions for 3 X 5:
..6..6..7..5..7....4..2..5..0..4....0..2..6..2..0....2..2..5..5..5
..2..0..1..1..1....7..1..6..3..7....6..6..0..6..6....5..5..2..2..2
..6..6..7..5..7....3..3..4..1..3....0..2..6..2..0....4..0..7..3..7

Crossrefs

Cf. A183680.

Sequence in context: A287383 A179732 A131353 * A015316 A212853 A127660

Adjacent sequences: A183674 A183675 A183676 * A183678 A183679 A183680

Keyword

nonn

Author

R. H. Hardin, Jan 06 2011

Status

approved