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%I #7 Apr 27 2023 15:05:27
%S 56,266,1187,4584,17010,58892,198325,642908,2043150,6344716,19418611,
%T 58538770,174569904,515123368,1507602967,4378408682,12635495950,
%U 36252368030,103495137889,294126992350,832586122466,2348335515958
%N Number of (n+1) X 2 0..2 arrays with rows and columns of permanents of all 2 X 2 subblocks lexicographically nondecreasing, and all 2 X 2 permanents nonzero.
%C Column 1 of A205235.
%H R. H. Hardin, <a href="/A205228/b205228.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 5*a(n-1) +8*a(n-2) -69*a(n-3) +389*a(n-5) -198*a(n-6) -1143*a(n-7) +865*a(n-8) +1830*a(n-9) -1686*a(n-10) -1468*a(n-11) +1612*a(n-12) +376*a(n-13) -616*a(n-14) +96*a(n-15).
%e Some solutions for n=4
%e ..2..2....0..1....2..0....0..1....0..2....1..2....1..1....2..1....1..0....2..2
%e ..0..2....2..2....0..2....2..0....2..0....1..2....1..0....0..2....2..1....0..1
%e ..2..1....2..1....2..0....1..1....1..2....2..1....1..2....2..2....1..1....2..0
%e ..1..2....2..2....1..2....0..2....1..2....2..2....2..1....1..1....2..1....2..1
%e ..2..2....1..2....1..2....2..2....1..2....2..2....2..2....2..2....1..2....0..2
%Y Cf. A205235.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 24 2012