A223062 T(n,k)=Number of nXk 0..3 arrays with all horizontally or vertically connected equal values in a straight line, and new values 0..3 introduced in row major order.
1, 2, 2, 5, 10, 5, 15, 114, 114, 15, 51, 1473, 4865, 1473, 51, 187, 19360, 213469, 213469, 19360, 187, 715, 255045, 9383963, 31331820, 9383963, 255045, 715, 2795, 3361024, 412602889, 4606719559, 4606719559, 412602889, 3361024, 2795, 11051, 44294253
Offset: 1
Examples
Some solutions for n=3 k=4 ..0..1..0..1....0..1..0..2....0..1..0..2....0..1..0..1....0..1..1..0 ..2..2..0..1....2..1..0..2....2..3..0..2....2..1..2..2....0..2..3..0 ..3..3..3..3....2..3..1..0....2..1..2..0....3..2..3..0....0..2..0..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..127
Crossrefs
Column 1 is A007581(n-1)
Formula
Empirical for column k:
k=1: a(n) = 7*a(n-1) -14*a(n-2) +8*a(n-3)
k=2: a(n) = 18*a(n-1) -71*a(n-2) +102*a(n-3) -48*a(n-4) for n>5
k=3: a(n) = 55*a(n-1) -515*a(n-2) +1337*a(n-3) -696*a(n-4) -1188*a(n-5) +1008*a(n-6) for n>7
k=4: [order 11 for n>12]
Comments