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A139673
Number of n X n symmetric binary matrices with all row sums 6.
3
1, 232, 66178, 24243520, 11234051976, 6549149852112, 4762109992158288, 4274712091685443584, 4686484162304929219950, 6209619146419137708859600, 9845751579221258486943505348, 18509102695712474753650903363840, 40904306737052771732376660591663712
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OFFSET
6,2
LINKS
Andrew Howroyd, Table of n, a(n) for n = 6..25
CROSSREFS
Column k=6 of A333157 and row 6 of A188448.
Sequence in context: A207053 A207130 A125850 * A252003 A151629 A301828
Adjacent sequences: A139670 A139671 A139672 * A139674 A139675 A139676
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 February 17 23:27 EST 2025. Contains 380976 sequences.
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