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A224621 Number of (n+4) X 8 0..2 matrices with each 5 X 5 subblock idempotent. 1
32029, 22081, 26624, 29254, 30723, 31623, 39450, 51956, 66929, 83137, 100012, 124474, 161207, 212671, 280106, 364172, 472461, 617237, 813236, 1076422, 1423431, 1878479, 2478058, 3273384, 4331649, 5736669, 7596488, 10055630, 13309847 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A224625.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..40

FORMULA

Empirical: a(n) = 3*a(n-1) - 2*a(n-2) - 2*a(n-3) + 3*a(n-4) - 2*a(n-6) + 2*a(n-8) - a(n-9) for n>13.

Empirical g.f.: x*(32029 - 74006*x + 24439*x^2 + 57602*x^3 - 55716*x^4 - 15033*x^5 + 48721*x^6 + 14698*x^7 - 49772*x^8 + 16668*x^9 + 300*x^10 + 64*x^11 + 4*x^12) / ((1 - x)^3*(1 + x)*(1 - x + x^2)*(1 - x^2 - x^3)). - Colin Barker, Sep 02 2018

EXAMPLE

Some solutions for n=2:

..1..1..1..1..1..1..0..2....0..1..0..0..0..0..0..0....1..0..0..0..0..0..0..2

..0..0..0..0..0..0..0..0....0..1..0..0..0..0..0..2....1..0..0..0..0..0..0..2

..0..0..0..0..0..0..0..0....0..1..0..0..0..0..0..1....2..0..0..0..0..0..0..1

..0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..1....2..0..0..0..0..0..0..1

..0..0..0..0..0..0..0..0....0..1..0..0..0..0..0..1....2..0..0..0..0..0..0..1

..1..1..0..2..1..1..1..1....0..1..0..0..0..0..0..1....1..0..0..0..0..0..0..1

CROSSREFS

Cf. A224625.

Sequence in context: A269318 A269319 A197114 * A231613 A054038 A156977

Adjacent sequences:  A224618 A224619 A224620 * A224622 A224623 A224624

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 12 2013

STATUS

approved

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Last modified October 5 05:10 EDT 2022. Contains 357252 sequences. (Running on oeis4.)