login
A240371
Number of nX2 0..3 arrays with no element equal to one plus the sum of elements to its left or one plus the sum of elements above it or zero plus the sum of the elements diagonally to its northwest, modulo 4
1
3, 11, 21, 67, 155, 353, 998, 2256, 5639, 14624, 34169, 87040, 216484, 522354, 1320708, 3242252, 7968236, 19928605, 48905783, 121065218, 300575628, 739878493, 1834210821, 4538220894, 11200994822, 27751051195, 68588966317, 169541251841
OFFSET
1,1
COMMENTS
Column 2 of A240376
LINKS
FORMULA
Empirical: a(n) = 3*a(n-2) +10*a(n-3) -3*a(n-4) -6*a(n-5) -3*a(n-6) +8*a(n-7) -7*a(n-8) -9*a(n-9) -4*a(n-10) +13*a(n-11) -14*a(n-12) +17*a(n-13) -a(n-15) for n>17
EXAMPLE
Some solutions for n=4
..3..2....3..3....3..3....3..2....3..3....3..2....3..3....2..2....3..2....3..2
..2..0....3..2....3..2....3..2....3..1....2..1....3..1....2..1....3..1....3..1
..3..1....2..0....2..0....2..0....2..2....3..1....2..0....3..1....2..2....2..2
..3..1....3..1....3..3....3..3....2..1....2..2....2..0....3..2....2..0....2..1
CROSSREFS
Sequence in context: A327607 A034185 A184053 * A158653 A129215 A139593
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 04 2014
STATUS
approved