A251287 Number of (n+1)X(3+1) 0..1 arrays with every 2X2 subblock having a single 1 or two 1s on the same edge or main diagonally

52, 219, 822, 3390, 12954, 52474, 202882, 813336, 3168621, 12623928, 49416048, 196129247, 770019542, 3049031658, 11992662293, 47418860005, 186721692802, 737641381117, 2906639008138, 11476362571548, 45241436664983

Offset

1,1

Comments

Column 3 of A251292

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +17*a(n-2) -25*a(n-3) -74*a(n-4) +87*a(n-5) +108*a(n-6) -77*a(n-7) -72*a(n-8) +15*a(n-9) +18*a(n-10) +2*a(n-11)

Example

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

Crossrefs

Sequence in context: A211564 A346825 A346858 * A023417 A122239 A086860

Adjacent sequences: A251284 A251285 A251286 * A251288 A251289 A251290

Keyword

nonn

Author

R. H. Hardin, Dec 01 2014

Status

approved