A204358 Number of (n+2)X7 0..1 arrays with every 3X3 subblock having three equal elements in a row horizontally, vertically, diagonally or antidiagonally exactly one way, and new values 0..1 introduced in row major order

7580, 16792, 35690, 71465, 174154, 412860, 901622, 2013562, 4631014, 10741246, 24250558, 54895662, 124980670, 286185464, 650745046, 1479976784, 3367789342, 7679928184, 17482919110, 39803180062, 90607144520, 206396554876

Offset

1,1

Comments

Column 5 of A204361

Links

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

Formula

Empirical: a(n) = 3*a(n-1) -4*a(n-2) +5*a(n-3) +9*a(n-4) -31*a(n-5) +49*a(n-6) -59*a(n-7) +15*a(n-8) +54*a(n-9) -102*a(n-10) +110*a(n-11) -52*a(n-12) -25*a(n-13) +74*a(n-14) -77*a(n-15) +38*a(n-16) +2*a(n-17) -18*a(n-18) +17*a(n-19) -8*a(n-20) +a(n-21) for n>30

Example

Some solutions for n=3
..0..1..1..1..0..0..0....0..0..0..1..1..0..0....0..0..0..1..1..1..1
..0..1..0..1..0..1..0....0..1..0..1..0..0..1....0..1..0..1..0..0..1
..1..0..1..0..1..0..1....1..0..1..0..0..1..0....1..0..1..0..0..1..0
..0..0..1..1..1..0..0....1..0..0..0..1..1..0....1..0..0..1..1..1..0
..1..0..0..1..0..0..1....1..1..0..1..1..0..0....1..1..0..0..1..0..0

Crossrefs

Sequence in context: A254909 A254902 A257204 * A232547 A028539 A234204

Adjacent sequences: A204355 A204356 A204357 * A204359 A204360 A204361

Keyword

nonn

Author

R. H. Hardin Jan 14 2012

Status

approved