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A156526 Number of n X n arrays of squares of integers, symmetric about both diagonal and antidiagonal, with all rows summing to 81. 0
1, 2, 8, 184, 772, 77184, 641136, 2194362732 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..8.

CROSSREFS

Sequence in context: A317794 A009377 A181234 * A009505 A305737 A028368

Adjacent sequences:  A156523 A156524 A156525 * A156527 A156528 A156529

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 09 2009

STATUS

approved

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Last modified November 26 09:38 EST 2020. Contains 338639 sequences. (Running on oeis4.)