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%I #5 Mar 31 2012 12:35:54
%S 557,6887,74148,864671,9764363,112439612,1284649009,14750484447,
%T 169027656900,1939448495087,22241611726431,255158474995768,
%U 2926771174469677,33574663298792895,385137356737681316
%N Half the number of (n+1)X7 binary arrays with no 2X2 subblock having exactly 2 ones
%C Column 6 of A183782
%H R. H. Hardin, <a href="/A183779/b183779.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n)=17*a(n-1)+68*a(n-2)-2331*a(n-3)+2715*a(n-4)+127282*a(n-5)-407543*a(n-6)-3552923*a(n-7)+16967238*a(n-8)+53329851*a(n-9)-373159393*a(n-10)-374852552*a(n-11)+5020944360*a(n-12)-530953324*a(n-13)-44088857196*a(n-14)+35340877520*a(n-15)+260439199152*a(n-16)-343900816832*a(n-17)-1042238954144*a(n-18)+1873164312128*a(n-19)+2773317482368*a(n-20)-6583718366464*a(n-21)-4584267066368*a(n-22)+15516200251392*a(n-23)+3621536735232*a(n-24)-24598780526592*a(n-25)+1537459224576*a(n-26)+25766309396480*a(n-27)-6673413963776*a(n-28)-17180213116928*a(n-29)+6712291491840*a(n-30)+6848728006656*a(n-31)-3277395591168*a(n-32)-1448477720576*a(n-33)+776315338752*a(n-34)+120259084288*a(n-35)-68719476736*a(n-36)
%e Some solutions with a(1,1)=0 for 3X7
%e ..0..0..1..1..0..0..0....0..1..1..1..1..1..1....0..1..1..0..1..1..1
%e ..0..1..1..1..1..0..0....0..0..1..1..1..1..0....1..1..1..1..1..1..1
%e ..0..0..1..1..0..0..1....0..1..1..1..1..0..0....0..1..1..0..1..1..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 07 2011