A303718 Number of n X 7 0..1 arrays with every element unequal to 0, 1 or 5 king-move adjacent elements, with upper left element zero.
21, 23, 40, 161, 361, 741, 1592, 3469, 7416, 15880, 34193, 73457, 157645, 338676, 727589, 1562584, 3356196, 7209121, 15484337, 33258365, 71436088, 153437805, 329568008, 707878984, 1520453793, 3265780153, 7014565013, 15066579716
Offset: 1
Keywords
Examples
Some solutions for n=5 ..0..0..1..0..0..0..0. .0..0..1..0..0..0..0. .0..1..0..0..0..0..0 ..0..0..0..0..0..0..0. .0..0..0..0..0..0..1. .0..0..0..0..0..0..1 ..0..0..0..0..0..0..0. .0..0..0..0..0..0..0. .0..0..0..0..0..0..0 ..0..0..0..0..0..0..0. .1..0..0..0..0..0..0. .0..0..0..0..0..0..0 ..0..0..0..0..1..0..0. .0..0..0..0..0..0..0. .0..0..1..0..0..0..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A303719.
Formula
Empirical: a(n) = a(n-1) +a(n-2) +3*a(n-3) +a(n-4) -a(n-5) -a(n-6) for n>9
Comments