A208197 Number of nX4 0..3 arrays with new values 0..3 introduced in row major order and no element equal to more than two of its immediate leftward or upward or left-upward diagonal neighbors.
15, 2653, 639701, 156617480, 38372808893, 9402035642924, 2303673397508915, 564442821781056268, 138298988287411669755, 33885824084409470445384, 8302657077306720410135797, 2034305388933816797435987804
Offset: 1
Keywords
Examples
Some solutions for n=4 ..0..0..0..1....0..0..0..1....0..1..1..0....0..0..0..1....0..0..0..0 ..0..1..1..0....1..1..0..0....0..0..2..0....0..1..0..2....0..1..1..2 ..0..1..2..3....2..3..3..0....0..2..1..1....2..1..0..3....1..0..1..3 ..3..0..3..1....0..2..1..3....3..1..0..0....1..0..1..0....1..3..3..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Formula
Empirical: a(n) = 236*a(n-1) +2368*a(n-2) -37526*a(n-3) -310734*a(n-4) +811712*a(n-5) +1791667*a(n-6) -2516274*a(n-7) -1895184*a(n-8) +2138400*a(n-9) -373248*a(n-10) for n>11
Comments