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A252569 Number of (n+2)X(3+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 1 2 5 6 or 7 and every 3X3 column and antidiagonal sum not equal to 1 2 5 6 or 7.

%I A252569 #6 Jun 02 2025 11:23:16
%S A252569 1069,1795,4168,10885,34532,96099,275252,896803,2561903,7521424,
%T A252569 25021976,72374863,214845510,722910315,2103362049,6276229910,
%U A252569 21234443167,61951956820,185297812626,628515657355,1835985520369,5497328348638
%N A252569 Number of (n+2)X(3+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 1 2 5 6 or 7 and every 3X3 column and antidiagonal sum not equal to 1 2 5 6 or 7.
%C A252569 Column 3 of A252574
%H A252569 R. H. Hardin, <a href="/A252569/b252569.txt">Table of n, a(n) for n = 1..210</a>
%F A252569 Empirical: a(n) = 57*a(n-3) -1068*a(n-6) +8828*a(n-9) -37486*a(n-12) +91215*a(n-15) -139676*a(n-18) +143042*a(n-21) -98725*a(n-24) +44005*a(n-27) -11816*a(n-30) +1746*a(n-33) -124*a(n-36) +3*a(n-39) for n>46
%e A252569 Some solutions for n=4
%e A252569 ..0..2..0..0..2....2..0..0..1..1....1..0..0..1..0....1..0..0..2..0
%e A252569 ..1..1..3..1..2....0..2..0..0..1....0..2..0..0..2....0..1..0..0..2
%e A252569 ..2..0..0..2..0....2..2..3..2..2....2..2..3..2..2....2..2..3..2..1
%e A252569 ..0..2..0..0..1....2..0..0..2..0....1..0..0..2..0....2..0..0..2..0
%e A252569 ..1..2..3..2..2....0..2..0..0..1....0..1..0..0..2....0..2..0..0..2
%e A252569 ..2..0..0..1..0....1..2..3..1..2....2..2..3..1..2....1..1..3..2..1
%K A252569 nonn
%O A252569 1,1
%A A252569 _R. H. Hardin_, Dec 18 2014