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%I #7 Apr 08 2020 01:56:04
%S 1,35150,133721189,46259653191,4893373431575,212962858290086,
%T 5406415387421647,87098380004205128,1034209337638242207,
%U 9323807379913081007,69112259378483785503,425995640129266136995,2291562702094516094937,10801522912361264775797,46064488469672007773725
%N Number of 7 X 7 0..n symmetric arrays with all rows summing to floor(n*7/2).
%e Some solutions for n=4
%e ..2..2..1..2..2..4..1....1..2..2..4..2..0..3....4..4..0..0..3..0..3
%e ..2..4..4..4..0..0..0....2..0..2..3..1..2..4....4..4..0..2..3..0..1
%e ..1..4..3..3..3..0..0....2..2..4..1..4..0..1....0..0..1..1..4..4..4
%e ..2..4..3..4..0..0..1....4..3..1..1..0..2..3....0..2..1..0..3..4..4
%e ..2..0..3..0..1..4..4....2..1..4..0..2..4..1....3..3..4..3..0..1..0
%e ..4..0..0..0..4..2..4....0..2..0..2..4..4..2....0..0..4..4..1..3..2
%e ..1..0..0..1..4..4..4....3..4..1..3..1..2..0....3..1..4..4..0..2..0
%Y Row 7 of A213800.
%K nonn
%O 0,2
%A _R. H. Hardin_, Jun 20 2012
%E a(0)=1 prepended and terms a(6) and beyond from _Andrew Howroyd_, Apr 07 2020
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