A235279 Number of (n+1) X (9+1) 0..4 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 5 (constant-stress 1 X 1 tilings).

35200, 41500, 48328, 62800, 79480, 115480, 160888, 260680, 401560, 716200, 1215928, 2348200, 4345240, 8936680, 17733688, 38288680, 80144920, 179655400, 391244728, 902914600, 2024143000, 4777083880, 10935717688, 26248208680

Offset

1,1

Links

R. H. Hardin, Table of n, a(n) for n = 1..31

Formula

Empirical: a(n) = a(n-1) +15*a(n-2) -15*a(n-3) -80*a(n-4) +80*a(n-5) +180*a(n-6) -180*a(n-7) -144*a(n-8) +144*a(n-9).

Example

Some solutions for n=5:
  0 4 0 1 0 2 0 3 0 4       1 3 1 3 1 3 1 4 1 3
  4 3 4 0 4 1 4 2 4 3       3 0 3 0 3 0 3 1 3 0
  0 4 0 1 0 2 0 3 0 4       0 2 0 2 0 2 0 3 0 2
  4 3 4 0 4 1 4 2 4 3       3 0 3 0 3 0 3 1 3 0
  0 4 0 1 0 2 0 3 0 4       1 3 1 3 1 3 1 4 1 3
  4 3 4 0 4 1 4 2 4 3       4 1 4 1 4 1 4 2 4 1

Crossrefs

Column 9 of A235280.

Sequence in context: A085545 A031855 A186567 * A358856 A133282 A257724

Adjacent sequences: A235276 A235277 A235278 * A235280 A235281 A235282

Keyword

nonn

Author

R. H. Hardin, Jan 05 2014

Status

approved