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%I #4 Apr 24 2013 08:52:41
%S 253,1935,12641,113261,979821,9045373,82894903,768456167,7112825923,
%T 65968698193,611639117173,5672921683137,52612656431953,
%U 487979068798433,4525916701502467,41977528928082105,389337361830188511
%N Number of (n+1)X3 0..2 matrices with each 2X2 permanent equal
%C Column 2 of A225027
%H R. H. Hardin, <a href="/A225021/b225021.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 18*a(n-1) -50*a(n-2) -745*a(n-3) +4314*a(n-4) +9186*a(n-5) -105283*a(n-6) +25054*a(n-7) +1280251*a(n-8) -1742965*a(n-9) -8687898*a(n-10) +19526759*a(n-11) +32128538*a(n-12) -112791204*a(n-13) -46192053*a(n-14) +383508114*a(n-15) -96539514*a(n-16) -782622789*a(n-17) +556582824*a(n-18) +907171190*a(n-19) -1065928104*a(n-20) -465301022*a(n-21) +1019495948*a(n-22) -75774692*a(n-23) -460095348*a(n-24) +170353464*a(n-25) +64111672*a(n-26) -41996720*a(n-27) +2265472*a(n-28) +1450752*a(n-29) -135168*a(n-30)
%e Some solutions for n=2
%e ..1..0..0....2..1..1....2..0..1....2..2..2....0..0..0....0..0..2....2..0..2
%e ..1..0..2....2..0..2....2..0..0....1..0..1....0..0..2....0..0..1....1..0..1
%e ..0..0..1....2..1..0....0..0..2....0..2..2....1..0..0....2..0..1....1..0..1
%K nonn
%O 1,1
%A _R. H. Hardin_ Apr 24 2013