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%I #4 Dec 08 2014 20:04:57
%S 1280,1664,3072,6144,11834,22632,44792,86988,170432,342826,673546,
%T 1333808,2714614,5407074,10855306,22352610,45191680,92075992,
%U 191833122,393688208,813894868,1714886756,3570500704,7482636226,15926322646
%N Number of (n+2)X(1+2) 0..3 arrays with no row, column, diagonal or antidiagonal in any 3X3 subblock summing to 2 3 6 or 7
%C Column 1 of A251791
%H R. H. Hardin, <a href="/A251784/b251784.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) +2*a(n-2) +14*a(n-3) -29*a(n-4) -39*a(n-5) -60*a(n-6) +103*a(n-7) +261*a(n-8) +219*a(n-9) +54*a(n-10) -679*a(n-11) -1209*a(n-12) -512*a(n-13) +491*a(n-14) +1546*a(n-15) +1721*a(n-16) +293*a(n-17) -756*a(n-18) -463*a(n-19) +513*a(n-20) +1705*a(n-21) +1590*a(n-22) -297*a(n-23) -1862*a(n-24) -1774*a(n-25) -161*a(n-26) +1644*a(n-27) +1852*a(n-28) +334*a(n-29) -1340*a(n-30) -1888*a(n-31) -1090*a(n-32) +44*a(n-33) +608*a(n-34) +484*a(n-35) +32*a(n-36) -352*a(n-37) -424*a(n-38) -336*a(n-39) -192*a(n-40) -48*a(n-41) for n>50
%e Some solutions for n=4
%e ..0..3..2....1..3..0....2..1..2....1..2..2....1..0..0....3..0..1....3..1..0
%e ..3..2..0....1..3..1....0..0..0....2..0..3....0..0..1....0..1..3....1..3..1
%e ..1..0..3....2..3..0....3..3..3....2..2..0....0..0..0....2..3..0....1..0..3
%e ..0..3..2....1..3..0....2..1..2....0..3..1....0..0..0....2..0..2....3..2..0
%e ..3..2..0....2..3..0....0..0..0....2..0..3....0..0..1....1..2..2....0..3..1
%e ..1..0..3....2..3..0....2..0..3....3..1..0....1..0..0....1..3..1....1..0..3
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 08 2014
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