login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A235297
Number of (n+1) X (7+1) 0..3 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 3 (constant-stress 1 X 1 tilings).
1
13376, 15692, 18832, 25592, 35936, 58688, 97888, 187184, 358016, 768272, 1623712, 3817232, 8702336, 22073168, 53248288, 143248784, 359277056, 1006831952, 2588024992, 7443849872, 19416695936, 56737632848, 149263917088, 440317917584
OFFSET
1,1
COMMENTS
Column 7 of A235301.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) +17*a(n-2) -57*a(n-3) -86*a(n-4) +372*a(n-5) +76*a(n-6) -972*a(n-7) +360*a(n-8) +864*a(n-9) -576*a(n-10).
EXAMPLE
Some solutions for n=5:
2 3 1 3 0 3 0 0 3 0 2 1 2 0 1 1 3 0 0 0 3 0 0 3
2 0 1 0 0 0 0 3 2 2 1 3 1 2 0 3 0 0 3 0 0 0 3 3
2 3 1 3 0 3 0 0 3 0 2 1 2 0 1 1 3 0 0 0 3 0 0 3
2 0 1 0 0 0 0 3 2 2 1 3 1 2 0 3 0 0 3 0 0 0 3 3
2 3 1 3 0 3 0 0 3 0 2 1 2 0 1 1 3 0 0 0 3 0 0 3
2 0 1 0 0 0 0 3 2 2 1 3 1 2 0 3 3 3 0 3 3 3 0 0
CROSSREFS
Sequence in context: A185503 A333014 A205196 * A252240 A220060 A207048
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 05 2014
STATUS
approved