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A234984
Number of (n+1) X (1+1) 0..5 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 2, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).
1
90, 370, 1640, 7554, 35072, 163416, 762002, 3554334, 16580250, 77345792, 360815494, 1683196556, 7852080772, 36629820538, 170877487282, 797140579074, 3718647299872, 17347426713674, 80925452066672, 377515864606272
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) + 6*a(n-2) - 33*a(n-3) - 24*a(n-4) + 56*a(n-5) + 34*a(n-6) - 20*a(n-7) - 4*a(n-8).
Empirical g.f.: 2*x*(45 - 40*x - 375*x^2 + 52*x^3 + 916*x^4 + 346*x^5 - 324*x^6 - 60*x^7) / ((1 - 2*x^2)*(1 - 5*x - 4*x^2 + 23*x^3 + 16*x^4 - 10*x^5 - 2*x^6)). - Colin Barker, Oct 16 2018
EXAMPLE
Some solutions for n=4:
0 1 3 0 4 5 0 1 3 2 2 1 1 2 1 2 5 2 3 2
1 0 2 1 2 1 3 2 4 1 4 5 5 4 4 3 1 0 4 5
4 5 1 2 5 2 4 1 1 0 2 1 2 3 3 4 0 1 1 4
0 3 0 3 1 0 3 2 4 5 5 2 1 0 2 1 5 4 0 1
1 2 1 2 2 3 4 1 0 3 4 3 2 3 3 0 0 1 1 4
CROSSREFS
Column 1 of A234991.
Sequence in context: A157888 A201103 A234991 * A158490 A304618 A187300
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 02 2014
STATUS
approved