A208553 Number of nX6 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 0 1 1 vertically.
26, 676, 3354, 16641, 50052, 150544, 351140, 819025, 1634430, 3261636, 5853246, 10504081, 17449544, 28987456, 45403272, 71115489, 106340130, 159012100, 229010210, 329821921, 460490316, 642926736, 874503084, 1189491121, 1582286342
Offset: 1
Keywords
Examples
Some solutions for n=4 ..0..1..0..1..0..1....1..0..1..0..1..0....1..1..1..1..0..1....0..1..0..1..0..1 ..1..1..1..1..1..1....1..1..0..1..0..0....0..1..0..1..0..0....0..1..0..1..1..1 ..0..1..0..1..0..1....1..0..1..0..1..0....0..1..1..1..0..0....0..1..0..1..0..0 ..0..1..1..0..1..1....0..1..0..1..0..0....0..1..0..1..0..0....0..1..0..1..0..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Formula
Empirical: a(n) = 2*a(n-1) +6*a(n-2) -14*a(n-3) -14*a(n-4) +42*a(n-5) +14*a(n-6) -70*a(n-7) +70*a(n-9) -14*a(n-10) -42*a(n-11) +14*a(n-12) +14*a(n-13) -6*a(n-14) -2*a(n-15) +a(n-16)
Comments