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A224688
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Number of (n+4) X 10 0..1 matrices with each 5 X 5 subblock idempotent.
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1
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5385, 2110, 2354, 2646, 2926, 3158, 3819, 4858, 6192, 7747, 9470, 11789, 15081, 19640, 25686, 33386, 43335, 56505, 74162, 97792, 129048, 170178, 224402, 296206, 391562, 518095, 685678, 907404, 1200852, 1589573, 2104743, 2787411, 3691719
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OFFSET
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1,1
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LINKS
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FORMULA
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Empirical: a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) + a(n-5) - 3*a(n-6) + 3*a(n-7) - a(n-8) for n>12.
Empirical g.f.: x*(5385 - 19430*x + 26224*x^2 - 15650*x^3 + 3411*x^4 - 5361*x^5 + 14558*x^6 - 12707*x^7 + 3439*x^8 + 69*x^9 + 57*x^10 + 4*x^11) / ((1 - x)^3*(1 - x + x^2)*(1 - x^2 - x^3)). - Colin Barker, Sep 03 2018
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EXAMPLE
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Some solutions for n=2:
..1..0..0..0..0..0..0..0..0..1....1..0..0..0..0..0..0..0..0..0
..1..0..0..0..0..0..0..0..0..0....1..0..0..0..0..0..0..0..0..0
..0..0..0..0..0..0..0..0..0..1....1..0..0..0..0..0..0..0..0..0
..0..0..0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..0..0..0
..1..0..0..0..0..0..0..0..0..1....1..0..0..0..0..0..0..0..0..1
..0..0..0..0..0..0..0..0..0..1....1..0..0..0..0..0..0..0..0..1
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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