A239594 Number of n X 2 0..3 arrays with no element equal to zero plus the sum of elements to its left or one plus the sum of elements above it or one plus the sum of the elements diagonally to its northwest or one plus the sum of the elements antidiagonally to its northeast, modulo 4.

4, 3, 4, 4, 5, 7, 8, 11, 12, 16, 19, 24, 30, 36, 46, 55, 70, 85, 106, 131, 161, 201, 246, 307, 377, 468, 578, 714, 885, 1091, 1353, 1669, 2067, 2554, 3158, 3907, 4827, 5974, 7381, 9132, 11288, 13959, 17262, 21340, 26394, 32628, 40353, 49890, 61693, 76284, 94321

Offset

1,1

Links

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

Formula

Empirical: a(n) = a(n-2) + a(n-5) for n>6.

Empirical g.f.: x*(4 + 3*x + x^3 + x^4 - x^5) / (1 - x^2 - x^5). - Colin Barker, Oct 26 2018

Example

All solutions for n=4:
..2..0....2..0....3..0....2..0
..2..0....2..0....2..3....2..0
..3..0....2..0....3..2....3..0
..2..3....2..0....2..3....3..2

Crossrefs

Column 2 of A239599.

Sequence in context: A010652 A332810 A088752 * A094948 A332472 A049788

Adjacent sequences: A239591 A239592 A239593 * A239595 A239596 A239597

Keyword

nonn

Author

R. H. Hardin, Mar 22 2014

Status

approved