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A261291
Number of (n+2)X(7+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000001 00010101 or 01010101.
1
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
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
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 14 2015
STATUS
approved