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A224624
Number of (n+4) X 11 0..2 matrices with each 5 X 5 subblock idempotent.
1
54070, 31702, 36576, 39450, 41120, 42214, 50748, 64133, 80045, 97220, 115074, 141044, 179978, 234400, 305570, 394164, 508295, 660924, 867536, 1144876, 1510365, 1989537, 2620887, 3458395, 4572786, 6052206, 8010335, 10599348, 14025400
OFFSET
1,1
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*(54070 - 184578*x + 234188*x^2 - 132922*x^3 + 30038*x^4 - 54238*x^5 + 137896*x^6 - 114285*x^7 + 29507*x^8 + 264*x^9 + 52*x^10 + 5*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..0....1..0..0..0..0..1..0..0..0..0..1
..1..0..0..0..0..0..0..0..0..0..0....1..0..0..0..0..1..0..0..0..0..0
..0..0..0..0..0..0..0..0..0..0..0....1..0..0..0..0..1..0..0..0..0..2
..2..0..0..0..0..0..0..0..0..0..0....2..0..0..0..0..1..0..0..0..0..1
..2..0..0..0..0..0..0..0..0..0..1....0..0..0..0..0..1..0..0..0..0..1
..2..0..0..0..0..0..0..0..0..0..1....1..0..0..0..0..1..0..0..0..0..1
CROSSREFS
Column 7 of A224625.
Sequence in context: A190472 A038564 A243362 * A202467 A224617 A224625
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 12 2013
STATUS
approved