A208637 T(n,k)=Number of nXk 0..1 arrays with new values 0..1 introduced in row major order and no element equal to more than one of its immediate leftward or upward or right-upward antidiagonal neighbors.
1, 2, 2, 4, 5, 4, 8, 11, 13, 8, 16, 23, 32, 34, 16, 32, 47, 71, 95, 89, 32, 64, 95, 150, 225, 284, 233, 64, 128, 191, 309, 494, 722, 851, 610, 128, 256, 383, 628, 1042, 1652, 2331, 2552, 1597, 256, 512, 767, 1267, 2149, 3577, 5572, 7548, 7655, 4181, 512, 1024, 1535
Offset: 1
Examples
Some solutions for n=4 k=3 ..0..0..0....0..0..1....0..1..1....0..0..1....0..0..1....0..1..0....0..1..0 ..1..1..0....1..0..1....1..0..1....1..0..1....1..0..1....1..0..1....1..0..1 ..0..1..1....0..1..0....0..1..0....0..1..0....1..0..0....0..1..0....1..0..1 ..0..0..1....1..0..1....0..1..0....0..1..0....1..1..0....1..0..1....1..0..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..1193
Formula
Empirical for column k:
k=1: a(n) = 2*a(n-1)
k=2: a(n) = 3*a(n-1) -a(n-2)
k=3: a(n) = 4*a(n-1) -3*a(n-2)
k=4: a(n) = 5*a(n-1) -6*a(n-2) +a(n-3)
k=5: a(n) = 6*a(n-1) -10*a(n-2) +4*a(n-3)
k=6: a(n) = 7*a(n-1) -15*a(n-2) +10*a(n-3) -a(n-4)
k=7: a(n) = 8*a(n-1) -21*a(n-2) +20*a(n-3) -5*a(n-4)
Empirical for row n:
n=1: a(k)=2*a(k-1)
n=2: a(k)=3*a(k-1)-2*a(k-2)
n=3: a(k)=4*a(k-1)-5*a(k-2)+2*a(k-3)
n=4: a(k)=5*a(k-1)-9*a(k-2)+7*a(k-3)-2*a(k-4) for k>5
n=5: a(k)=6*a(k-1)-14*a(k-2)+16*a(k-3)-9*a(k-4)+2*a(k-5) for k>7
n=6: a(k)=7*a(k-1)-20*a(k-2)+30*a(k-3)-25*a(k-4)+11*a(k-5)-2*a(k-6) for k>9
n=7: a(k)=8*a(k-1)-27*a(k-2)+50*a(k-3)-55*a(k-4)+36*a(k-5)-13*a(k-6)+2*a(k-7) for k>11
Comments