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%I #7 Sep 03 2018 11:39:09
%S 6713,2591,2862,3214,3540,3819,4572,5723,7181,8868,10729,13235,16781,
%T 21671,28131,36332,46916,60920,79685,104778,137937,181542,239010,
%U 315099,416134,550178,727674,962482,1273220,1684831,2230321,2953139,3910594
%N Number of (n+4) X 11 0..1 matrices with each 5 X 5 subblock idempotent.
%H R. H. Hardin, <a href="/A224689/b224689.txt">Table of n, a(n) for n = 1..210</a>
%F 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.
%F 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
%e Some solutions for n=2:
%e ..1..0..0..0..0..1..0..0..0..0..0....0..1..0..0..0..0..0..0..0..0..0
%e ..1..0..0..0..0..1..0..0..0..0..1....0..1..0..0..0..0..0..0..0..0..0
%e ..0..0..0..0..0..1..0..0..0..0..0....0..1..0..0..0..0..0..0..0..0..0
%e ..0..0..0..0..0..1..0..0..0..0..0....0..1..0..0..0..0..0..0..0..1..0
%e ..1..0..0..0..0..1..0..0..0..0..1....0..0..0..0..0..0..0..0..0..1..0
%e ..1..0..0..0..0..1..0..0..0..0..1....0..0..0..0..0..0..0..0..0..1..0
%Y Column 7 of A224690.
%K nonn
%O 1,1
%A _R. H. Hardin_, Apr 15 2013
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