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A181209
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Number of n X 5 binary matrices with no two 1's adjacent diagonally or antidiagonally.
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1
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32, 169, 2117, 17424, 177073, 1630729, 15786848, 149352841, 1429585373, 13610488896, 129934154497, 1238878076401, 11819811992192, 112736763711049, 1075437390934037, 10258292274099984, 97854335246290033, 933422273708422969
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OFFSET
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1,1
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COMMENTS
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Column 5 of A181212.
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LINKS
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Robert Israel, Table of n, a(n) for n = 1..1019 (n = 1..250 from R. H. Hardin)
Robert Israel, Maple-assisted proof of formula
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FORMULA
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Empirical: a(n) = 12*a(n-1) - 283*a(n-3) + 516*a(n-4) + 600*a(n-5) - 1415*a(n-6) + 600*a(n-8) - 125*a(n-9).
Formula verified by Robert Israel, Dec 25 2017 (see link).
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MAPLE
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f:= gfun:-rectoproc({a(n)=12*a(n-1)-283*a(n-3)+516*a(n-4)+600*a(n-5)-1415*a(n-6)+600*a(n-8)-125*a(n-9), a(1) = 32, a(2) = 169, a(3) = 2117, a(4) = 17424, a(5) = 177073, a(6) = 1630729, a(7) = 15786848, a(8) = 149352841, a(9)=1429585373}, a(n), remember):
map(f, [$1..30]); # Robert Israel, Dec 25 2017
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CROSSREFS
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Sequence in context: A302413 A303180 A188820 * A231299 A029534 A120046
Adjacent sequences: A181206 A181207 A181208 * A181210 A181211 A181212
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KEYWORD
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nonn
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AUTHOR
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R. H. Hardin, Oct 10 2010
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STATUS
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approved
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