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A156487
Number of n X n arrays of squares of integers, symmetric about both diagonal and antidiagonal, with all rows summing to 27.
0
3, 58, 204, 13400, 102762, 19311868, 365142544, 166203280736, 6303614816380
OFFSET
3,1
CROSSREFS
Sequence in context: A037107 A335293 A041735 * A254653 A243510 A024218
KEYWORD
nonn
AUTHOR
R. H. Hardin Feb 09 2009
STATUS
approved