login
A240390
Number of nX3 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 two plus the sum of the elements diagonally to its northwest, modulo 4
1
1, 7, 32, 258, 1232, 10291, 48826, 405404, 1922824, 15957927, 75674424, 627937288, 2977619007, 24707220314, 117158008335, 972128626445, 4609679165199, 38249153789915, 181371291266288, 1504941221689915, 7136186544470695
OFFSET
1,2
COMMENTS
Column 3 of A240394
LINKS
FORMULA
Empirical: a(n) = 63*a(n-2) -1109*a(n-4) +7143*a(n-6) -395*a(n-8) -201246*a(n-10) +762860*a(n-12) +347011*a(n-14) -7366154*a(n-16) +11744674*a(n-18) +3758987*a(n-20) +10095295*a(n-22) -126415852*a(n-24) +204390541*a(n-26) -65238786*a(n-28) -59211883*a(n-30) -114625640*a(n-32) +381020006*a(n-34) -342073760*a(n-36) +16725276*a(n-38) +181283664*a(n-40) -110895680*a(n-42) +16492080*a(n-44) +1175136*a(n-46) +390464*a(n-48) for n>49
EXAMPLE
Some solutions for n=4
..3..0..0....3..0..0....3..0..0....3..0..0....3..0..0....3..0..0....3..0..0
..3..0..0....3..0..0....3..0..0....1..0..0....1..2..0....1..3..3....3..0..0
..1..2..2....1..2..0....1..2..0....3..0..2....3..2..0....3..1..2....1..0..0
..1..2..0....1..2..0....3..0..2....1..0..2....1..3..3....1..3..3....1..2..2
CROSSREFS
Sequence in context: A302995 A188331 A177766 * A024093 A110323 A288721
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 04 2014
STATUS
approved