A239988 Number of 4Xn 0..3 arrays with no element equal to zero plus the sum of elements to its left or two plus the sum of the elements above it or one plus the sum of the elements diagonally to its northwest, modulo 4

4, 16, 56, 171, 530, 1495, 4059, 10121, 23476, 51169, 105957, 210063, 401043, 740392, 1325954, 2309449, 3920715, 6500605, 10544919, 16762214, 26148867, 40085363, 60458446, 89814510, 131550423, 190148874, 271466315, 383082641, 534722915

Offset

1,1

Comments

Row 4 of A239986

Links

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

Formula

Empirical: a(n) = (1/907200)*n^10 - (1/72576)*n^9 + (113/120960)*n^8 - (265/12096)*n^7 + (2651/5400)*n^6 - (141761/17280)*n^5 + (40878671/362880)*n^4 - (10305217/9072)*n^3 + (399085217/50400)*n^2 - (86061371/2520)*n + 68243 for n>12

Example

Some solutions for n=4
..3..0..0..0....3..0..0..0....3..0..0..0....3..0..0..0....3..0..0..0
..2..1..0..0....2..3..0..3....2..1..0..0....2..1..0..0....2..3..0..3
..2..0..0..3....2..0..0..0....2..0..0..0....2..0..3..0....2..0..1..0
..3..2..0..2....2..0..0..0....3..2..0..0....3..0..0..1....3..2..0..3

Crossrefs

Sequence in context: A212520 A115108 A127393 * A308288 A340257 A261386

Adjacent sequences: A239985 A239986 A239987 * A239989 A239990 A239991

Keyword

nonn

Author

R. H. Hardin, Mar 30 2014

Status

approved