A264476 T(n,k)=Number of (n+1)X(k+1) arrays of permutations of 0..(n+1)*(k+1)-1 with each element having directed index change 0,1 1,0 2,1 or -1,-1.
0, 1, 1, 0, 2, 0, 0, 4, 4, 1, 1, 8, 6, 8, 1, 0, 17, 16, 16, 16, 1, 0, 36, 57, 120, 49, 32, 2, 1, 76, 160, 456, 456, 124, 64, 2, 0, 160, 484, 2272, 3540, 2232, 384, 128, 3, 0, 337, 1449, 11044, 28489, 24773, 10116, 1041, 256, 4, 1, 710, 4250, 49200, 215607, 310748
Offset: 1
Examples
Some solutions for n=4 k=4 ..6..0..1..9..3....6..0..1..2..3....6..7..8..9..3....6..7..8..2..3 .11..5..2..7..4...11.12.13.14..4....0..1..2.14..4....0..1.13.14..4 .16.10.18..8.13....5.10..7.19..9...16.10.11.19.13...16.17.11.12..9 .21.22.23.24.14...21.22.16.24..8...21..5.12.24.18...10..5.23.24.18 .15.20.17.12.19...15.20.17.18.23...15.20.17.22.23...15.20.21.22.19
Links
- R. H. Hardin, Table of n, a(n) for n = 1..220
Formula
Empirical for column k:
k=1: a(n) = a(n-2) +a(n-3)
k=2: a(n) = 2*a(n-1)
k=3: [order 15]
k=4: a(n) = 18*a(n-2) +36*a(n-3) -45*a(n-4) -216*a(n-5) -243*a(n-6) for n>7
k=5: [order 84] for n>86
k=6: [order 36] for n>40
Empirical for row n:
n=1: a(n) = a(n-3)
n=2: a(n) = 2*a(n-1) +a(n-4)
n=3: [order 15]
n=4: [order 10] for n>11
n=5: [order 84]
Comments