A181260 - OEIS

%I #3 Mar 31 2012 12:35:49

%S 21024,27554,36244,48846,79324,133850,242784,526226,1196428,2877078,

%T 7542964,20219426,55452024,157207034,449767204,1298801406,3801296524,

%U 11170281290,32957815824,97800035426,290736856828,865851794598

%N Number of (n+2)X8 binary matrices with every 3X3 block having exactly four 1's

%C Column 6 of A181262

%H R. H. Hardin, <a href="/A181260/b181260.txt">Table of n, a(n) for n=1..93</a>

%F Empirical: a(n)=6*a(n-1)-11*a(n-2)+42*a(n-3)-216*a(n-4)+396*a(n-5)-719*a(n-6)+3018*a(n-7)-5533*a(n-8)+6498*a(n-9)-20880*a(n-10)+38280*a(n-11)-33444*a(n-12)+75384*a(n-13)-138204*a(n-14)+97848*a(n-15)-134784*a(n-16)+247104*a(n-17)-150336*a(n-18)+93312*a(n-19)-171072*a(n-20)+93312*a(n-21)

%e Some solutions for 4X8

%e ..0..1..0..1..1..0..1..0....1..1..0..1..0..0..1..1....1..1..0..1..1..0..1..1

%e ..1..0..0..0..0..0..0..0....1..0..1..1..1..1..0..0....0..0..0..0..0..0..0..1

%e ..1..0..1..1..0..1..1..1....0..0..0..0..0..0..1..0....1..1..0..1..1..0..1..0

%e ..0..1..0..1..1..0..1..0....0..1..1..0..0..1..0..1....1..1..0..1..1..0..1..1

%K nonn

%O 1,1

%A _R. H. Hardin_ Oct 10 2010