A297298 Number of nX7 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 2 neighboring 1s.
1, 9, 32, 130, 600, 2816, 13504, 65521, 319835, 1566612, 7687400, 37759082, 185561978, 912173296, 4484666199, 22050441495, 108423345160, 533136119034, 2621552944596, 12890861627884, 63387955860276, 311696797461453
Offset: 1
Keywords
Examples
Some solutions for n=5 ..0..0..0..0..0..0..0. .0..1..1..0..0..0..0. .0..0..0..1..1..1..0 ..0..0..1..1..1..1..0. .1..1..0..0..0..0..0. .0..0..1..0..1..1..1 ..0..1..0..0..1..1..1. .0..0..0..0..0..0..0. .0..1..0..0..0..1..1 ..1..1..1..0..0..1..0. .0..1..1..0..0..1..1. .1..1..1..1..0..1..0 ..0..1..1..1..1..0..0. .1..1..0..0..1..1..0. .0..0..1..1..1..0..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A297299.
Formula
Empirical: a(n) = 7*a(n-1) -6*a(n-2) -26*a(n-3) +18*a(n-4) +37*a(n-5) -25*a(n-7) -9*a(n-8) -6*a(n-9) -2*a(n-10) +6*a(n-11) +5*a(n-12) for n>14
Comments