A305047 T(n,k)=Number of nXk 0..1 arrays with every element unequal to 0, 2, 3, 6 or 7 king-move adjacent elements, with upper left element zero.
1, 1, 1, 1, 4, 1, 1, 7, 7, 1, 1, 13, 5, 13, 1, 1, 26, 9, 9, 26, 1, 1, 49, 15, 11, 15, 49, 1, 1, 99, 17, 20, 20, 17, 99, 1, 1, 194, 40, 17, 55, 17, 40, 194, 1, 1, 387, 73, 25, 201, 201, 25, 73, 387, 1, 1, 773, 87, 70, 337, 137, 337, 70, 87, 773, 1, 1, 1538, 219, 67, 1359, 42, 42, 1359
Offset: 1
Examples
Some solutions for n=5 k=4 ..0..1..0..0. .0..0..0..0. .0..0..1..0. .0..1..1..0. .0..0..0..1 ..1..1..0..0. .1..1..1..1. .1..1..0..1. .0..1..1..0. .0..0..0..1 ..0..0..0..0. .1..1..1..1. .1..1..1..1. .0..1..1..0. .0..0..0..1 ..0..1..0..0. .1..1..1..1. .1..1..0..0. .0..1..1..0. .0..0..0..1 ..1..0..1..1. .1..1..1..1. .1..1..0..1. .0..1..1..0. .0..0..0..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..287
Crossrefs
Column 2 is A304004.
Formula
Empirical for column k:
k=1: a(n) = a(n-1)
k=2: a(n) = a(n-1) +3*a(n-2) -4*a(n-4) for n>5
k=3: [order 11] for n>13
k=4: [order 9] for n>13
Comments