A232958 Number of 4Xn 0..3 arrays with no element x(i,j) adjacent to value 3-x(i,j) horizontally, diagonally or antidiagonally, and top left element zero.
64, 1029, 27441, 685251, 17429409, 442227825, 11228712351, 285082486341, 7238105184837, 183771148650939, 4665845904118053, 118463173683294573, 3007712801760687567, 76364121654785540601, 1938841730920089921489
Offset: 1
Keywords
Examples
Some solutions for n=3 ..0..1..0....0..1..0....0..2..0....0..0..0....0..1..3....0..2..0....0..1..1 ..0..1..3....3..2..0....2..0..2....2..2..0....3..1..0....3..2..0....1..1..3 ..0..2..3....0..2..2....2..2..2....3..2..3....0..2..3....3..2..0....3..1..0 ..3..2..0....0..2..3....2..3..3....0..1..0....3..1..3....3..1..0....3..2..3
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Formula
Empirical: a(n) = 24*a(n-1) +76*a(n-2) -1008*a(n-3) -992*a(n-4) +8762*a(n-5) -7403*a(n-6) -2174*a(n-7) +3324*a(n-8) -416*a(n-9) -96*a(n-10)
Comments