%I #4 Apr 11 2013 08:46:42
%S 2185738,164935,125525,122508,128620,138581,146715,156428,171787,
%T 199628,251449,337387,463685,642049,872565,1156493,1513357,1983382,
%U 2631002,3556586,4890506,6786490,9424850,13019794,17851883,24336233,33091332
%N Number of (n+6)X7 0..1 matrices with each 7X7 subblock idempotent
%C Column 1 of A224588
%H R. H. Hardin, <a href="/A224581/b224581.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-3) +a(n-5) +a(n-7) +2*a(n-8) +3*a(n-9) +2*a(n-10) -2*a(n-13) -2*a(n-14) -3*a(n-15) -2*a(n-16) -4*a(n-17) -3*a(n-18) -2*a(n-19) +a(n-21) +2*a(n-22) +2*a(n-23) +a(n-24) +a(n-25) +a(n-26) +a(n-27) for n>39
%e Some solutions for n=2
%e ..1..0..1..1..0..1..0....0..0..0..0..0..0..0....0..0..0..0..0..0..0
%e ..0..0..1..0..1..1..0....0..0..1..1..0..0..0....0..1..0..0..1..1..0
%e ..0..0..0..0..0..0..0....0..0..0..0..0..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..0..0
%e ..0..0..1..0..1..1..0....0..0..0..0..0..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..0..0
%e ..0..0..1..0..1..1..0....0..0..0..0..0..0..0....0..1..0..0..1..1..0
%e ..0..0..1..0..1..1..0....0..0..1..1..0..0..0....0..1..1..1..0..0..1
%K nonn
%O 1,1
%A _R. H. Hardin_ Apr 11 2013