A230589 Number of nX3 0..5 arrays x(i,j) with each element horizontally or vertically next to at least one element with value (x(i,j)+1) mod 6, and upper left element zero

0, 2, 28, 270, 2966, 34684, 405122, 4682406, 53977396, 622617950, 7184471690, 82901373580, 956544304506, 11036808012474, 127345448758460, 1469346402844134, 16953716335937734, 195616511948606684

Offset

1,2

Comments

Column 3 of A230592

Links

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

Formula

Empirical: a(n) = 25*a(n-1) -240*a(n-2) +1314*a(n-3) -4747*a(n-4) +11211*a(n-5) -17017*a(n-6) +28739*a(n-7) -79128*a(n-8) +115064*a(n-9) +19357*a(n-10) -100001*a(n-11) -204372*a(n-12) +250392*a(n-13) +78184*a(n-14) +59884*a(n-15) +82996*a(n-16) +34212*a(n-17) +19496*a(n-18) +1304*a(n-19) -608*a(n-20)

Example

Some solutions for n=3
..0..1..2....0..1..0....0..1..2....0..1..0....0..5..4....0..5..4....0..5..4
..5..4..3....5..2..5....5..4..3....1..2..5....1..4..1....1..2..3....1..4..3
..4..3..2....4..3..2....2..3..2....2..3..4....2..3..2....0..5..4....2..3..2

Crossrefs

Sequence in context: A230270 A230759 A229581 * A097353 A092801 A281320

Adjacent sequences: A230586 A230587 A230588 * A230590 A230591 A230592

Keyword

nonn

Author

R. H. Hardin, Oct 24 2013

Status

approved