A207603 Number of 6Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 1 and 1 0 1 vertically.
12, 144, 396, 1089, 6765, 42025, 157440, 589824, 3005184, 15311569, 64177113, 268992801, 1274751324, 6041020176, 26465410620, 115943655025, 534003435845, 2459467656361, 10969953831936, 48929241563136, 222765694221312
Offset: 1
Keywords
Examples
Some solutions for n=4 ..1..0..0..1....0..1..1..0....0..1..1..1....1..0..1..1....1..1..0..1 ..0..0..1..1....1..1..1..0....0..1..1..0....1..1..0..1....1..1..0..0 ..0..0..1..1....0..1..1..0....0..1..1..0....1..1..0..1....1..1..0..0 ..0..0..1..1....0..1..1..0....0..1..1..0....1..0..0..1....1..1..0..0 ..0..0..1..1....0..1..1..0....0..1..1..0....1..0..0..1....1..1..0..0 ..0..0..1..1....0..1..1..0....0..1..1..0....1..0..0..1....1..1..0..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Formula
Empirical: a(n) = a(n-1) -5*a(n-2) +26*a(n-3) +226*a(n-4) +190*a(n-5) +1260*a(n-6) -6300*a(n-8) -4750*a(n-9) -28250*a(n-10) -16250*a(n-11) +15625*a(n-12) -15625*a(n-13) +78125*a(n-14)
Comments