A207734 Number of 7Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 0 1 vertically.
31, 961, 2449, 6241, 88243, 1247689, 4799749, 18464209, 184732327, 1848226081, 8873643337, 42603849649, 355158126283, 2960701807561, 16146759616669, 88059474768001, 662598445609375, 4985683837890625, 29297113012890625
Offset: 1
Keywords
Examples
Some solutions for n=4 ..0..0..1..1....1..0..0..1....1..0..0..1....1..1..1..1....0..0..1..1 ..0..1..1..1....1..1..0..1....1..0..0..1....0..0..1..1....0..1..1..1 ..1..0..1..1....1..0..0..1....1..1..0..1....0..0..1..1....0..0..1..1 ..0..0..1..1....1..0..0..1....1..0..0..1....1..0..1..1....1..0..1..1 ..0..0..1..1....1..0..0..1....1..0..0..1....0..1..1..1....0..1..1..1 ..1..0..1..1....1..1..0..1....1..0..0..1....0..0..1..1....0..0..1..1 ..0..1..1..0....1..0..1..1....1..0..1..1....1..0..1..1....1..0..0..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Formula
Empirical: a(n) = a(n-1) +48*a(n-3) +1512*a(n-4) +180*a(n-5) +612*a(n-6) -15840*a(n-7) -496179*a(n-8) -159489*a(n-9) +110160*a(n-10) +986580*a(n-11) +48988800*a(n-12) +17204400*a(n-13) +52488000*a(n-15) -1049760000*a(n-16)
Comments