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%I #8 Sep 02 2018 06:46:08
%S 43489,24252,28949,31623,33115,34032,42214,55189,70669,87402,104808,
%T 130151,168223,221528,291318,378265,490305,640166,843080,1115531,
%U 1474675,1945604,2566138,3389329,4484713,5938982,7863920,10409131,13777271
%N Number of (n+4) X 10 0..2 matrices with each 5 X 5 subblock idempotent.
%C Column 6 of A224625.
%H R. H. Hardin, <a href="/A224623/b224623.txt">Table of n, a(n) for n = 1..38</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*(43489 - 149704*x + 192875*x^2 - 112617*x^3 + 26798*x^4 - 43723*x^5 + 113448*x^6 - 96972*x^7 + 26141*x^8 + 195*x^9 + 65*x^10 + 4*x^11) / ((1 - x)^3*(1 - x + x^2)*(1 - x^2 - x^3)). - _Colin Barker_, Sep 02 2018
%e Some solutions for n=2:
%e ..1..0..0..0..0..0..0..0..0..0....1..0..0..0..0..0..0..0..0..1
%e ..1..0..0..0..0..0..0..0..0..1....1..0..0..0..0..0..0..0..0..2
%e ..0..0..0..0..0..0..0..0..0..2....0..0..0..0..0..0..0..0..0..1
%e ..2..0..0..0..0..0..0..0..0..1....2..0..0..0..0..0..0..0..0..0
%e ..0..0..0..0..0..0..0..0..0..1....1..0..0..0..0..0..0..0..0..1
%e ..0..0..0..0..0..0..0..0..0..1....1..0..0..0..0..0..0..0..0..1
%Y Cf. A224625.
%K nonn
%O 1,1
%A _R. H. Hardin_, Apr 12 2013