A208685 Number of nX5 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 1 1 and 1 0 1 vertically.
16, 256, 768, 2889, 12096, 41013, 133207, 444912, 1448128, 4616800, 14733663, 46884096, 148366461, 468807885, 1480447408, 4669224000, 14715790096, 46366826149, 146050380000, 459933577353, 1448231824455, 4559797881648
Offset: 1
Keywords
Examples
Some solutions for n=4 ..0..1..1..1..1....0..1..1..1..1....0..1..0..1..1....1..1..0..1..1 ..0..1..0..1..0....1..1..1..1..0....1..1..1..1..1....1..1..1..1..0 ..1..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..1..0....0..1..0..1..0....0..1..0..1..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Formula
Empirical: a(n) = 4*a(n-1) -3*a(n-2) +10*a(n-3) -27*a(n-4) -6*a(n-5) -15*a(n-6) +51*a(n-7) +41*a(n-8) +31*a(n-9) -51*a(n-10) -29*a(n-11) -27*a(n-12) +15*a(n-13) +6*a(n-14) +3*a(n-15) -4*a(n-16) +a(n-17) +a(n-19)
Comments