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A224688 Number of (n+4) X 10 0..1 matrices with each 5 X 5 subblock idempotent. 1
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 (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*(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

EXAMPLE

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

CROSSREFS

Column 6 of A224690.

Sequence in context: A063408 A057850 A058325 * A328562 A126117 A190106

Adjacent sequences:  A224685 A224686 A224687 * A224689 A224690 A224691

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 15 2013

STATUS

approved

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Last modified March 29 17:23 EDT 2020. Contains 333116 sequences. (Running on oeis4.)