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Number of (n+2)X(4+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 1 3 6 or 7
1

%I #4 Dec 16 2014 17:30:01

%S 7815,2579,6011,23422,97191,409636,1741936,7424869,31630640,134638865,

%T 573240255,2441382936,10396958017,44272818260,188528191000,

%U 802834481773,3418801561062,14558580766571,61996115521347,264004067912514

%N Number of (n+2)X(4+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 1 3 6 or 7

%C Column 4 of A252321

%H R. H. Hardin, <a href="/A252317/b252317.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +6*a(n-2) +20*a(n-3) +54*a(n-4) +38*a(n-5) -41*a(n-6) -191*a(n-7) -285*a(n-8) +297*a(n-9) +752*a(n-10) -166*a(n-11) -811*a(n-12) -153*a(n-13) +296*a(n-14) +139*a(n-15) +173*a(n-16) +339*a(n-17) -299*a(n-18) -788*a(n-19) +163*a(n-20) +779*a(n-21) +92*a(n-22) -330*a(n-23) -98*a(n-24) +18*a(n-25) -54*a(n-26) +3*a(n-27) +35*a(n-28) -3*a(n-29) +12*a(n-30) +7*a(n-31) -4*a(n-32) for n>37

%e Some solutions for n=4

%e ..3..3..2..3..3..3....2..3..3..3..2..3....3..3..3..3..3..3....2..3..3..2..3..3

%e ..3..3..3..3..2..3....3..3..3..3..3..3....2..3..3..3..3..2....3..3..3..3..3..3

%e ..3..3..3..3..3..3....3..3..3..3..3..3....3..3..3..2..3..3....3..3..3..3..2..3

%e ..3..2..3..3..3..3....3..3..3..3..3..3....3..3..3..3..3..3....3..3..3..3..3..3

%e ..3..3..3..2..3..3....3..3..3..2..3..3....3..3..3..3..2..3....3..3..3..2..3..3

%e ..2..3..3..3..3..3....2..3..3..3..3..2....3..2..3..3..3..3....2..3..3..3..3..2

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 16 2014