A302682 Number of 4Xn 0..1 arrays with every element equal to 0, 1, 4 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
8, 6, 7, 20, 30, 76, 217, 509, 1189, 3034, 7569, 18274, 44932, 111561, 274057, 672217, 1657278, 4083105, 10038822, 24702412, 60827449, 149699125, 368356029, 906653234, 2231584641, 5492001706, 13516457764, 33267138281, 81875898241
Offset: 1
Keywords
Examples
Some solutions for n=5 ..0..1..1..1..0. .0..1..0..0..0. .0..1..1..1..0. .0..1..0..1..0 ..0..1..0..1..0. .0..1..0..1..0. .0..1..0..1..0. .0..1..0..1..0 ..0..1..0..0..0. .0..1..0..1..0. .0..0..0..1..0. .0..1..0..1..0 ..0..1..0..1..0. .0..1..0..1..0. .0..1..0..1..0. .0..1..0..1..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A302680.
Formula
Empirical: a(n) = a(n-1) +a(n-2) +5*a(n-3) +5*a(n-4) -3*a(n-5) -3*a(n-6) +2*a(n-7) for n>11
Comments