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

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

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

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

Adjacent sequences: A204486 A204487 A204488 * A204490 A204491 A204492

Keyword

nonn

Author

R. H. Hardin Jan 15 2012

Status

approved