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A234676
Number of (n+1) X (3+1) 0..5 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 5 (constant-stress 1 X 1 tilings).
1
1264, 2924, 6328, 17312, 43240, 129848, 354856, 1129256, 3265864, 10806344, 32397928, 110161352, 338146120, 1172415368, 3657091816, 12860973896, 40576496584, 144194315144, 458737409128, 1642863057992, 5259197091400
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 4*a(n-1) +47*a(n-2) -200*a(n-3) -901*a(n-4) +4204*a(n-5) +8957*a(n-6) -48440*a(n-7) -47194*a(n-8) +334096*a(n-9) +101948*a(n-10) -1410080*a(n-11) +170136*a(n-12) +3549696*a(n-13) -1446912*a(n-14) -4861440*a(n-15) +2954880*a(n-16) +2764800*a(n-17) -2073600*a(n-18).
EXAMPLE
Some solutions for n=5:
5 2 4 1 0 1 0 3 1 4 2 5 5 5 5 5 0 3 0 1
3 5 2 4 5 1 5 3 2 0 3 1 5 0 5 0 4 2 4 0
4 1 3 0 2 3 2 5 1 4 2 5 3 3 3 3 0 3 0 1
2 4 1 3 5 1 5 3 2 0 3 1 0 5 0 5 4 2 4 0
4 1 3 0 0 1 0 3 1 4 2 5 2 2 2 2 1 4 1 2
2 4 1 3 5 1 5 3 3 1 4 2 5 0 5 0 4 2 4 0
CROSSREFS
Column 3 of A234681.
Sequence in context: A252506 A205762 A331824 * A237327 A233887 A234147
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 29 2013
STATUS
approved