A208142 T(n,k)=Number of nXk 0..1 arrays avoiding 0 0 1 and 0 1 1 horizontally and 0 0 1 and 1 0 1 vertically.
2, 4, 4, 6, 16, 6, 9, 36, 36, 8, 12, 81, 108, 64, 10, 16, 144, 324, 240, 100, 12, 20, 256, 720, 900, 450, 144, 14, 25, 400, 1600, 2400, 2025, 756, 196, 16, 30, 625, 3000, 6400, 6300, 3969, 1176, 256, 18, 36, 900, 5625, 14000, 19600, 14112, 7056, 1728, 324, 20, 42, 1296
Offset: 1
Examples
Some solutions for n=4 k=3 ..1..0..0....0..0..0....0..1..0....1..1..1....0..1..0....0..1..0....0..1..0 ..0..0..0....1..0..0....1..1..0....1..1..0....1..0..0....0..1..0....1..0..1 ..0..0..0....0..0..0....1..1..0....1..0..0....1..0..0....0..1..0....0..0..0 ..0..0..0....0..0..0....1..0..0....1..0..0....1..0..0....0..1..0....0..0..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..4508
Crossrefs
Formula
Empirical for column k:
k=1: a(n) = 2*n
k=2: a(n) = 4*n^2
k=3: a(n) = 3*n^3 + 3*n^2
k=4: a(n) = (9/4)*n^4 + (9/2)*n^3 + (9/4)*n^2
k=5: a(n) = n^5 + 4*n^4 + 5*n^3 + 2*n^2
k=6: a(n) = (4/9)*n^6 + (8/3)*n^5 + (52/9)*n^4 + (16/3)*n^3 + (16/9)*n^2
k=7: a(n) = (5/36)*n^7 + (5/4)*n^6 + (155/36)*n^5 + (85/12)*n^4 + (50/9)*n^3 + (5/3)*n^2
Comments