A252135 - OEIS

%I #6 Jun 02 2025 10:50:19

%S 439,1183,5233,22766,96481,409028,1741344,7424211,31630024,134638253,

%T 573239601,2441382308,10396957389,44272817558,188528190392,

%U 802834481181,3418801560404,14558580765955,61996115520735,264004067911860

%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 3 4 6 or 7.

%C Column 4 of A252139

%H R. H. Hardin, <a href="/A252135/b252135.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) +5*a(n-2) +14*a(n-3) +34*a(n-4) -16*a(n-5) -79*a(n-6) -150*a(n-7) -94*a(n-8) +581*a(n-9) +457*a(n-10) -913*a(n-11) -631*a(n-12) +692*a(n-13) +433*a(n-14) -236*a(n-15) -116*a(n-16) +72*a(n-17) -57*a(n-18) -32*a(n-19) +38*a(n-20) -15*a(n-21) +5*a(n-22) +11*a(n-23) -4*a(n-24) for n>26

%e Some solutions for n=4

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 14 2014