A183674 Number of (n+1) X 2 0..7 arrays with every 2 X 2 subblock summing to 14.

344, 2080, 13448, 90784, 631784, 4497760, 32592008, 239551264, 1781373224, 13376585440, 101278522568, 772234051744, 5923974485864, 45683076481120, 353896909605128, 2752474657736224, 21482113227489704, 168170396980664800

Offset

1,1

Comments

Column 1 of A183680.

Links

R. H. Hardin, Table of n, a(n) for n = 1..189

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*(43 - 1288*x + 15799*x^2 - 102256*x^3 + 374218*x^4 - 766288*x^5 + 801072*x^6 - 322560*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 02 2018

Example

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

Crossrefs

Cf. A183680.

Sequence in context: A237378 A237243 A183680 * A245994 A246630 A250921

Adjacent sequences: A183671 A183672 A183673 * A183675 A183676 A183677

Keyword

nonn

Author

R. H. Hardin, Jan 06 2011

Status

approved