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A204734 Number of (n+1)X3 0..1 arrays with rows and columns of permanents of all 2X2 subblocks lexicographically nondecreasing, and all 2X2 permanents nonzero 1

%I

%S 15,43,115,304,787,2033,5219,13398,34331,87991,225395,577452,1479139,

%T 3789069,9705763,24862194,63685419,163134387,417876275,1070414056,

%U 2741919411,7023575913,17991253859,46085557838,118050573627,302392805359

%N Number of (n+1)X3 0..1 arrays with rows and columns of permanents of all 2X2 subblocks lexicographically nondecreasing, and all 2X2 permanents nonzero

%C Column 2 of A204740

%H R. H. Hardin, <a href="/A204734/b204734.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 4*a(n-1) -2*a(n-2) -8*a(n-3) +11*a(n-4) -4*a(n-5).

%F Empirical G.f.: x*(15-17*x-27*x^2+50*x^3-20*x^4)/((1-x)^3*(1-x-4*x^2)). [Colin Barker, Jan 19 2012]

%e Some solutions for n=4

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Jan 18 2012

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Last modified October 27 23:46 EDT 2021. Contains 348305 sequences. (Running on oeis4.)