%I #7 May 03 2021 14:54:08
%S 678,3354,18124,97316,518514,2764828,14778068,79010324,422170156,
%T 2255865816,12055912400,64428206472,344303766674,1839970274068,
%U 9832898770152,52547443489104,280815669383888,1500690900097558
%N Number of (n+2) X (1+2) 0..3 arrays with no row, column, diagonal or antidiagonal in any 3 X 3 subblock summing to 3 4 5 or 6.
%C Column 1 of A251836.
%H R. H. Hardin, <a href="/A251830/b251830.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) +8*a(n-2) +41*a(n-3) +68*a(n-4) +33*a(n-5) -207*a(n-6) -543*a(n-7) -471*a(n-8) -30*a(n-9) +202*a(n-10) -352*a(n-11) -548*a(n-12) +37*a(n-13) +640*a(n-14) +670*a(n-15) +347*a(n-16) +235*a(n-17) -124*a(n-18) -97*a(n-19) -106*a(n-20) -51*a(n-21) -56*a(n-22) +8*a(n-23) +4*a(n-24) +8*a(n-25) +4*a(n-27) for n > 29.
%e Some solutions for n=4
%e ..3..2..3....0..1..1....1..0..0....3..2..3....1..0..0....0..0..0....0..2..0
%e ..3..3..2....0..0..0....0..1..0....2..3..2....0..1..0....0..1..0....1..0..1
%e ..2..3..3....0..0..0....1..0..0....3..3..3....1..1..0....0..0..0....1..0..0
%e ..3..3..2....1..0..1....0..1..1....3..3..2....0..0..0....0..0..1....0..0..0
%e ..2..3..3....0..0..0....1..0..0....3..2..3....1..0..1....0..1..0....1..1..0
%e ..3..2..2....1..1..0....0..0..1....3..3..2....0..1..0....0..0..1....0..0..0
%Y Cf. A251836.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 09 2014
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