A205318 T(n,k)=Number of (n+1)X(k+1) 0..1 arrays with every 2X2 subblock having the same number of equal edges, and new values 0..1 introduced in row major order.
8, 20, 20, 56, 84, 56, 164, 376, 376, 164, 488, 1708, 2606, 1708, 488, 1460, 7784, 18152, 18152, 7784, 1460, 4376, 35500, 126536, 193664, 126536, 35500, 4376, 13124, 161928, 882182, 2068148, 2068148, 882182, 161928, 13124, 39368, 738636, 6150512
Offset: 1
Examples
Some solutions for n=4 k=3 ..0..1..1..0....0..0..1..0....0..0..1..0....0..0..1..0....0..1..0..0 ..1..1..0..0....0..1..1..1....1..1..1..1....0..1..1..1....1..1..0..1 ..0..0..0..1....1..1..0..1....0..1..0..1....0..0..0..0....1..0..0..1 ..0..1..1..1....1..0..0..1....0..1..0..0....1..0..1..0....0..0..1..1 ..0..1..0..0....1..1..0..1....0..1..1..0....0..0..0..0....0..1..1..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..420
Crossrefs
Column 1 is A115099.
Formula
Empirical for column k:
k=1: a(n) = 4*a(n-1) -3*a(n-2)
k=2: a(n) = 6*a(n-1) -7*a(n-2) +2*a(n-3)
k=3: a(n) = 10*a(n-1) -24*a(n-2) +21*a(n-3) -6*a(n-4)
k=4: a(n) = 17*a(n-1) -81*a(n-2) +157*a(n-3) -140*a(n-4) +56*a(n-5) -8*a(n-6)
k=5: a(n) = 31*a(n-1) -321*a(n-2) +1569*a(n-3) -4179*a(n-4) +6420*a(n-5) -5671*a(n-6) +2668*a(n-7) -516*a(n-8)
k=6: (order 14 recurrence)
k=7: (order 20 recurrence)
Comments