A283042 T(n,k)=Number of nXk 0..1 arrays with no 1 equal to more than one of its horizontal and vertical neighbors, with the exception of exactly one element.
0, 0, 0, 1, 4, 1, 2, 16, 16, 2, 5, 68, 119, 68, 5, 12, 256, 818, 818, 256, 12, 26, 924, 5065, 9152, 5065, 924, 26, 56, 3232, 30378, 94368, 94368, 30378, 3232, 56, 118, 11044, 175963, 931844, 1604067, 931844, 175963, 11044, 118, 244, 37104, 997302, 8912378
Offset: 1
Examples
Some solutions for n=4 k=4 ..0..0..1..0. .1..0..0..0. .1..0..1..0. .0..0..1..1. .1..0..0..1 ..1..0..1..0. .1..1..0..0. .0..1..1..1. .0..1..0..0. .0..1..0..1 ..0..0..1..0. .0..0..1..0. .1..0..1..0. .1..0..1..0. .0..1..0..1 ..1..0..0..0. .1..0..1..0. .1..0..0..0. .1..1..0..0. .0..0..0..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..220
Crossrefs
Column 1 is A073778(n-1).
Formula
Empirical for column k:
k=1: a(n) = 2*a(n-1) +a(n-2) -3*a(n-4) -2*a(n-5) -a(n-6)
k=2: a(n) = 4*a(n-1) +2*a(n-2) -12*a(n-3) -11*a(n-4) +4*a(n-5) +6*a(n-6) -a(n-8)
k=3: [order 18]
k=4: [order 30]
k=5: [order 72]
Comments