A261291 Number of (n+2)X(7+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000001 00010101 or 01010101.

1015, 1361, 4715, 14106, 48435, 153144, 561724, 1703644, 6132232, 19020918, 68690527, 210960310, 762494362, 2350497978, 8485691418, 26128594224, 94398007523, 290731525710, 1049987329395, 3233854822566, 11680868423504

Offset

1,1

Comments

Column 7 of A261292.

Links

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

Formula

Empirical: a(n) = 4*a(n-2) +72*a(n-4) +126*a(n-6) -504*a(n-8) -183*a(n-10) +2017*a(n-12) -433*a(n-14) -4301*a(n-16) +4487*a(n-18) -20226*a(n-20) +67671*a(n-22) -85069*a(n-24) +15742*a(n-26) +113631*a(n-28) -145965*a(n-30) -77933*a(n-32) +581282*a(n-34) -888710*a(n-36) +370130*a(n-38) +202679*a(n-40) -271169*a(n-42) +90087*a(n-44) +41519*a(n-46) -19825*a(n-48) +1820*a(n-50) +70*a(n-52) -892*a(n-54) -416*a(n-56) -64*a(n-58) for n>69

Example

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

Crossrefs

Cf. A261292.

Sequence in context: A096928 A234754 A023076 * A335969 A225717 A117807

Adjacent sequences: A261288 A261289 A261290 * A261292 A261293 A261294

Keyword

nonn

Author

R. H. Hardin, Aug 14 2015

Status

approved