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Number of (n+1) X 4 0..2 arrays with every 2 X 2 subblock having zero permanent.
1

%I #10 Jun 16 2018 16:03:00

%S 441,11025,110889,1896129,23707161,356190129,4803737481,69030731169,

%T 955680252921,13523866505361,188928681187689,2659384141993089,

%U 37267791691450329,523625523775949169,7345838128808607561

%N Number of (n+1) X 4 0..2 arrays with every 2 X 2 subblock having zero permanent.

%C Column 3 of A206472.

%H R. H. Hardin, <a href="/A206467/b206467.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 15*a(n-1) + 54*a(n-2) - 1116*a(n-3) + 1728*a(n-4) + 10368*a(n-5) - 20736*a(n-6).

%F Empirical g.f.: 9*x*(49 + 490*x - 8700*x^2 + 14400*x^3 + 91008*x^4 - 186624*x^5) / ((1 - 21*x + 108*x^2 - 144*x^3)*(1 + 6*x - 36*x^2 - 144*x^3)). - _Colin Barker_, Jun 16 2018

%e Some solutions for n=4:

%e 2 2 2 1 2 2 0 0 0 1 0 1 1 2 0 0 0 0 2 0

%e 0 0 0 0 0 0 0 1 0 2 0 2 0 0 0 2 0 0 2 0

%e 1 2 1 0 2 0 0 0 0 1 0 1 1 0 0 0 0 0 0 0

%e 0 0 0 0 2 0 0 1 0 1 0 1 0 0 1 0 2 2 1 0

%e 2 1 2 1 2 0 0 2 0 1 0 1 1 0 2 0 0 0 0 0

%Y Cf. A206472.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 08 2012