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A224623
Number of (n+4) X 10 0..2 matrices with each 5 X 5 subblock idempotent.
1
43489, 24252, 28949, 31623, 33115, 34032, 42214, 55189, 70669, 87402, 104808, 130151, 168223, 221528, 291318, 378265, 490305, 640166, 843080, 1115531, 1474675, 1945604, 2566138, 3389329, 4484713, 5938982, 7863920, 10409131, 13777271
OFFSET
1,1
COMMENTS
Column 6 of A224625.
LINKS
FORMULA
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*(43489 - 149704*x + 192875*x^2 - 112617*x^3 + 26798*x^4 - 43723*x^5 + 113448*x^6 - 96972*x^7 + 26141*x^8 + 195*x^9 + 65*x^10 + 4*x^11) / ((1 - x)^3*(1 - x + x^2)*(1 - x^2 - x^3)). - Colin Barker, Sep 02 2018
EXAMPLE
Some solutions for n=2:
..1..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....1..0..0..0..0..0..0..0..0..2
..0..0..0..0..0..0..0..0..0..2....0..0..0..0..0..0..0..0..0..1
..2..0..0..0..0..0..0..0..0..1....2..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..1
..0..0..0..0..0..0..0..0..0..1....1..0..0..0..0..0..0..0..0..1
CROSSREFS
Cf. A224625.
Sequence in context: A184382 A126771 A103875 * A210331 A233690 A205923
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 12 2013
STATUS
approved