A240377 Number of nX2 0..3 arrays with no element equal to zero plus the sum of elements to its left or two plus the sum of elements above it or zero plus the sum of the elements diagonally to its northwest, modulo 4

2, 10, 44, 148, 636, 2430, 9648, 37946, 149336, 588102, 2315310, 9114874, 35884720, 141278356, 556180846, 2189677956, 8620404070, 33937808062, 133609043358, 526004415056, 2070820187636, 8152588623474, 32095829706144, 126357695287702

Offset

1,1

Comments

Column 2 of A240381

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +11*a(n-2) -a(n-3) -39*a(n-4) -40*a(n-5) +3*a(n-6) +13*a(n-7) +64*a(n-8) +162*a(n-9) -220*a(n-10) +122*a(n-11) -38*a(n-12) -82*a(n-13) +60*a(n-14) for n>15

Example

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

Crossrefs

Sequence in context: A305657 A064835 A225958 * A025590 A122932 A080069

Adjacent sequences: A240374 A240375 A240376 * A240378 A240379 A240380

Keyword

nonn

Author

R. H. Hardin, Apr 04 2014

Status

approved