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A224689 Number of (n+4) X 11 0..1 matrices with each 5 X 5 subblock idempotent. 1
6713, 2591, 2862, 3214, 3540, 3819, 4572, 5723, 7181, 8868, 10729, 13235, 16781, 21671, 28131, 36332, 46916, 60920, 79685, 104778, 137937, 181542, 239010, 315099, 416134, 550178, 727674, 962482, 1273220, 1684831, 2230321, 2953139, 3910594 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

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*(6713 - 24261*x + 32776*x^2 - 19540*x^3 + 4205*x^4 - 6627*x^5 + 18090*x^6 - 15825*x^7 + 4297*x^8 + 120*x^9 + 44*x^10 + 5*x^11) / ((1 - x)^3*(1 - x + x^2)*(1 - x^2 - x^3)). - Colin Barker, Sep 03 2018

EXAMPLE

Some solutions for n=2:

..1..0..0..0..0..1..0..0..0..0..0....0..1..0..0..0..0..0..0..0..0..0

..1..0..0..0..0..1..0..0..0..0..1....0..1..0..0..0..0..0..0..0..0..0

..0..0..0..0..0..1..0..0..0..0..0....0..1..0..0..0..0..0..0..0..0..0

..0..0..0..0..0..1..0..0..0..0..0....0..1..0..0..0..0..0..0..0..1..0

..1..0..0..0..0..1..0..0..0..0..1....0..0..0..0..0..0..0..0..0..1..0

..1..0..0..0..0..1..0..0..0..0..1....0..0..0..0..0..0..0..0..0..1..0

CROSSREFS

Column 7 of A224690.

Sequence in context: A239565 A234242 A252602 * A190292 A164972 A190129

Adjacent sequences:  A224686 A224687 A224688 * A224690 A224691 A224692

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 15 2013

STATUS

approved

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Last modified June 16 11:12 EDT 2019. Contains 324152 sequences. (Running on oeis4.)