A156420 - OEIS

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A156420

Number of 15 X 15 arrays of squares of integers, symmetric under 90-degree rotation, with all rows summing to n.

%I #5 Oct 27 2019 21:37:45

%S 1,0,0,30693320,1890254100,0,0,686163316440,4354347220860,0,0,

%T 141370447642494,817218706478195,0,0

%N Number of 15 X 15 arrays of squares of integers, symmetric under 90-degree rotation, with all rows summing to n.

%K nonn

%O 0,4

%A _R. H. Hardin_, Feb 09 2009