A183675 Number of (n+1) X 3 0..7 arrays with every 2 X 2 subblock summing to 14.

2080, 10088, 54496, 316232, 1931680, 12267368, 80331616, 539328392, 3696942880, 25792417448, 182701863136, 1311449598152, 9524204728480, 69887478820328, 517576834025056, 3864851916885512, 29073925027240480, 220170830778612008

Offset

1,1

Comments

Column 2 of A183680.

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

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*(260 - 8099*x + 103376*x^2 - 696557*x^3 + 2654612*x^4 - 5661188*x^5 + 6161616*x^6 - 2580480*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 03 2018

Example

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

Crossrefs

Cf. A183680.

Sequence in context: A180921 A270537 A076581 * A178272 A194605 A233104

Adjacent sequences: A183672 A183673 A183674 * A183676 A183677 A183678

Keyword

nonn

Author

R. H. Hardin, Jan 06 2011

Status

approved