A208012 Number of nX7 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 0 1 and 0 1 1 vertically.
28, 784, 3808, 18496, 55624, 167281, 393049, 923521, 1860496, 3748096, 6791488, 12306064, 20630548, 34586161, 54628609, 86285521, 130008844, 195888016, 284062816, 411927616, 578699848, 812991169, 1112035513, 1521078001
Offset: 1
Keywords
Examples
Some solutions for n=4 ..1..1..0..0..1..0..0....0..0..1..1..0..0..1....0..1..1..1..1..1..1 ..1..1..1..0..0..1..0....1..1..1..0..0..1..0....0..0..1..1..1..1..1 ..0..1..0..0..1..0..0....0..0..1..1..0..0..1....0..0..1..0..0..1..0 ..0..0..1..0..0..1..0....1..1..1..0..0..1..0....0..0..1..1..0..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