A251288 Number of (n+1)X(4+1) 0..1 arrays with every 2X2 subblock having a single 1 or two 1s on the same edge or main diagonally

125, 701, 3390, 18924, 94706, 518711, 2645966, 14292754, 73763850, 394839392, 2052818979, 10924134430, 57063130832, 302529963932, 1585024760524, 8383254978829, 44005652384769, 232393583625579, 1221371767402917

Offset

1,1

Comments

Column 4 of A251292

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +40*a(n-2) -55*a(n-3) -533*a(n-4) +518*a(n-5) +3271*a(n-6) -2001*a(n-7) -10562*a(n-8) +2928*a(n-9) +17984*a(n-10) -637*a(n-11) -15411*a(n-12) -1198*a(n-13) +6419*a(n-14) +561*a(n-15) -1099*a(n-16) -18*a(n-17) +50*a(n-18) -2*a(n-19)

Example

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

Crossrefs

Sequence in context: A235896 A250634 A250944 * A060093 A253345 A016815

Adjacent sequences: A251285 A251286 A251287 * A251289 A251290 A251291

Keyword

nonn

Author

R. H. Hardin, Dec 01 2014

Status

approved