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A234698
Number of (n+1) X (2+1) 0..7 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
2628, 13952, 74308, 409268, 2261220, 12903164, 73793620, 434990348, 2565773508, 15562814252, 94270091668, 585903611948, 3628952476740, 23018623628204, 145209752122900, 936710697140588, 5998159579778628, 39231903137940332
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 15*a(n-1) +125*a(n-2) -2865*a(n-3) -1490*a(n-4) +219360*a(n-5) -507740*a(n-6) -8437740*a(n-7) +34905816*a(n-8) +161734320*a(n-9) -1006299360*a(n-10) -1062547200*a(n-11) +13887417600*a(n-12) -8926848000*a(n-13) -75188736000*a(n-14) +121927680000*a(n-15).
EXAMPLE
Some solutions for n=3:
7 3 3 1 6 4 5 2 3 4 1 4 0 2 1 3 1 0 6 6 1
6 7 2 4 4 7 5 7 3 3 5 3 0 7 1 7 0 4 6 1 1
5 1 1 2 7 5 6 3 4 4 1 4 4 6 5 4 2 1 6 6 1
5 6 1 0 0 3 2 4 0 3 5 3 3 0 4 3 6 0 7 2 2
CROSSREFS
Column 2 of A234702.
Sequence in context: A295482 A236621 A221941 * A190936 A020439 A254776
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 29 2013
STATUS
approved