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Number of (n+2)X(3+2) 0..3 arrays with every 3X3 subblock row and column sum not 3 or 6 and every diagonal and antidiagonal sum 3 or 6
1

%I #4 Dec 09 2014 12:48:48

%S 9354,28202,130826,397474,2395590,12830794,38456182,258040386,

%T 1458543158,4283605290,30490194918,176827937410,511836962950,

%U 3753133248778,22033777327254,63258118796290,471146262590358,2783208175723434

%N Number of (n+2)X(3+2) 0..3 arrays with every 3X3 subblock row and column sum not 3 or 6 and every diagonal and antidiagonal sum 3 or 6

%C Column 3 of A251829

%H R. H. Hardin, <a href="/A251824/b251824.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +18*a(n-2) +186*a(n-3) -295*a(n-4) -3581*a(n-5) -5476*a(n-6) +27712*a(n-7) +147781*a(n-8) -343417*a(n-9) -664334*a(n-10) +3685778*a(n-11) +11032159*a(n-12) -28166731*a(n-13) -219938272*a(n-14) +169643092*a(n-15) +1244674788*a(n-16) +245160672*a(n-17) -5143057600*a(n-18) -3556473440*a(n-19) +52452832512*a(n-20) -9748484352*a(n-21) -258140220416*a(n-22) -279686815744*a(n-23) +673789935616*a(n-24) +2333219938304*a(n-25) -1555844104192*a(n-26) -3672451776512*a(n-27) -3137051557888*a(n-28) +9117078913024*a(n-29) +4049554374656*a(n-30) -11741526228992*a(n-31) -3800173641728*a(n-32) +3334706561024*a(n-33) +16033649786880*a(n-34) -10475425234944*a(n-35) +11643656339456*a(n-36) -12300786335744*a(n-37) -1649267441664*a(n-38) +1649267441664*a(n-39) for n>42

%e Some solutions for n=3

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 09 2014