A301668 Number of nX7 0..1 arrays with every element equal to 1, 2 or 4 horizontally or vertically adjacent elements, with upper left element zero.
8, 421, 5289, 71564, 1073621, 15498505, 225780260, 3307561389, 48158543096, 703127937300, 10259186324647, 149696614458243, 2184338617470806, 31873058777880129, 465081902561442941, 6786326832276152384
Offset: 1
Keywords
Examples
Some solutions for n=5 ..0..0..0..1..1..0..0. .0..0..1..1..0..0..1. .0..0..0..1..1..0..1 ..0..1..1..0..0..1..1. .0..1..0..0..1..0..1. .0..1..0..0..1..0..1 ..0..0..1..0..1..0..1. .0..1..0..1..1..0..1. .0..1..1..0..1..1..0 ..1..0..1..0..1..0..1. .0..1..0..1..0..0..0. .0..0..0..1..0..1..0 ..1..1..0..0..1..0..1. .0..1..0..1..1..0..0. .1..1..0..1..0..1..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A301669.
Comments