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A204489
Number of (n+2)X7 0..1 arrays with every 3X3 subblock having three equal elements in a row horizontally, vertically or nw-to-se diagonally exactly one way, and new values 0..1 introduced in row major order
1
4664, 5804, 11331, 22341, 43620, 85756, 168567, 334451, 672081, 1366044, 2793653, 5734032, 11833402, 24484245, 50644733, 105122828, 218567557, 454101052, 945848184, 1972351215, 4109094663, 8578179471, 17922597153, 37410414881
OFFSET
1,1
COMMENTS
Column 5 of A204492
LINKS
FORMULA
Empirical: a(n) = a(n-1) +a(n-2) +9*a(n-3) -5*a(n-4) -10*a(n-5) -7*a(n-6) -28*a(n-7) +17*a(n-8) -10*a(n-9) +52*a(n-10) -a(n-11) +6*a(n-12) -3*a(n-13) -14*a(n-14) +3*a(n-15) -17*a(n-16) +7*a(n-17) +4*a(n-18) -2*a(n-19) -4*a(n-21) +2*a(n-22) for n>32
EXAMPLE
Some solutions for n=3
..0..0..0..1..0..0..0....0..1..0..0..1..1..0....0..0..0..0..1..1..0
..0..1..0..0..1..0..1....1..1..1..0..0..1..1....0..1..1..0..0..1..1
..1..0..1..0..0..1..1....1..0..1..1..0..0..1....1..1..0..1..0..0..1
..0..1..0..1..0..0..0....0..1..0..1..1..0..0....0..1..1..0..1..0..1
..0..0..1..0..1..0..1....0..1..1..0..1..1..0....0..0..1..1..0..1..1
CROSSREFS
Sequence in context: A020422 A048131 A062626 * A252127 A188364 A236014
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 15 2012
STATUS
approved