A264550 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 -1,1 -1,2 1,0 or 0,-1.
0, 1, 1, 1, 2, 0, 1, 6, 5, 0, 1, 16, 16, 10, 1, 3, 40, 36, 45, 21, 0, 3, 96, 172, 216, 133, 44, 0, 4, 240, 764, 1528, 1160, 400, 93, 1, 6, 608, 2728, 11728, 14852, 4640, 1204, 196, 0, 9, 1536, 9880, 66372, 163744, 105081, 23140, 3561, 413, 0, 12, 3840, 38818, 403920
Offset: 1
Examples
Some solutions for n=4 k=4 ..1..2..5..6..7....1..2..3..4..7....1..2..3..7..8....1..5..3..6..8 ..0.10..8..3..4....0.10..8.11.12....0.10.11.12..4....0..7..2.12..4 .11.12.15.14..9....5..6.13.17..9....5..6.13.17..9...11.15.13.14..9 .16.20.18.13.23...16.20.18.21.14...16.20.18.21.14...10.20.18.22.23 .21.22.17.24.19...15.22.23.24.19...15.22.23.24.19...21.16.17.24.19
Links
- R. H. Hardin, Table of n, a(n) for n = 1..198
Crossrefs
Row 1 is A080013(n+1).
Formula
Empirical for column k:
k=1: a(n) = a(n-3)
k=2: a(n) = 2*a(n-1) +a(n-4)
k=3: [order 15]
k=4: [order 10] for n>11
k=5: [order 84]
Empirical for row n:
n=1: a(n) = a(n-2) +a(n-3) +a(n-4) -a(n-6)
n=2: a(n) = 2*a(n-1) +8*a(n-4)
n=3: [order 70]
n=4: [order 56] for n>59
Comments