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Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and column sum 2 4 5 or 7 and every diagonal and antidiagonal sum not 2 4 5 or 7
1

%I #4 Dec 11 2014 06:33:43

%S 1194,1914,2524,3260,5810,8932,12872,21518,33814,52274,97880,163006,

%T 292472,517966,988740,1737754,3522210,6326974,12849382,23480004,

%U 48494960,88704266,185430256,340660550,713811996,1315598042,2766156180,5101490134

%N Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and column sum 2 4 5 or 7 and every diagonal and antidiagonal sum not 2 4 5 or 7

%C Column 1 of A251923

%H R. H. Hardin, <a href="/A251916/b251916.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) +3*a(n-2) +7*a(n-3) -19*a(n-4) -55*a(n-5) +10*a(n-6) +50*a(n-7) +364*a(n-8) -117*a(n-9) -6*a(n-10) -882*a(n-11) -502*a(n-12) +53*a(n-13) -1051*a(n-14) +4258*a(n-15) +42*a(n-16) +10108*a(n-17) -4620*a(n-18) -6404*a(n-19) -18017*a(n-20) -26531*a(n-21) +19834*a(n-22) -98*a(n-23) +80589*a(n-24) +10240*a(n-25) +38889*a(n-26) -35365*a(n-27) -118241*a(n-28) -66111*a(n-29) -162464*a(n-30) +123466*a(n-31) +98156*a(n-32) +285095*a(n-33) +131300*a(n-34) -95238*a(n-35) -177590*a(n-36) -324987*a(n-37) -42871*a(n-38) +28426*a(n-39) +184986*a(n-40) +155430*a(n-41) +33986*a(n-42) +4968*a(n-43) -76159*a(n-44) -44351*a(n-45) -43296*a(n-46) -13598*a(n-47) +18184*a(n-48) +20308*a(n-49) +20054*a(n-50) +2314*a(n-51) -5832*a(n-52) -6468*a(n-53) -2632*a(n-54) +1136*a(n-55) +1080*a(n-56) +344*a(n-57) -96*a(n-58) -80*a(n-59) for n>63

%e Some solutions for n=4

%e ..0..0..2....2..2..3....2..2..0....3..3..1....2..0..0....3..1..0....3..2..0

%e ..3..2..2....2..0..0....1..1..2....1..0..1....1..0..3....1..3..0....1..2..1

%e ..2..2..1....0..3..1....2..2..3....0..2..3....1..2..1....0..0..2....1..0..1

%e ..2..1..1....3..1..3....2..2..0....3..2..0....3..2..0....3..2..2....2..3..2

%e ..1..1..0....1..3..0....1..1..2....1..0..1....0..1..3....2..2..1....2..1..2

%e ..1..3..3....3..0..2....2..2..3....1..0..3....2..1..2....2..1..1....3..1..3

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 11 2014