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A139671 Number of n X n symmetric binary matrices with all row sums 5. 3
1, 76, 6912, 848932, 133948836, 26615510712, 6549149852112, 1966499966796816, 711040444591249476, 305907023641901084832, 154921887640109512226304, 91469751377953081098144816, 62419855497729620428436222688, 48849705066296300911892229634944 (list; graph; refs; listen; history; text; internal format)
OFFSET

5,2

LINKS

Andrew Howroyd, Table of n, a(n) for n = 5..25

CROSSREFS

Column k=5 of A333157 and row 5 of A188448.

Sequence in context: A049669 A198476 A234778 * A098606 A093276 A184290

Adjacent sequences:  A139668 A139669 A139670 * A139672 A139673 A139674

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jun 12 2008

EXTENSIONS

Terms a(13) and beyond from Andrew Howroyd, Mar 09 2020

STATUS

approved

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Last modified December 9 08:41 EST 2021. Contains 349627 sequences. (Running on oeis4.)