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A362823 Number of labeled magmas with n elements satisfying the identities (xy)y = x and (xy)z = (xz)y. 4
1, 1, 4, 22, 976, 19376, 7680016, 430723168, 1489656111616, 214815786486400, 6364561150037368576, 2241692646969785651456, 566719960584895502028138496, 471612192582034433034750951424, 1008512943343839231897776246546624512, 1936475539456937172034340659334701398016 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
COMMENTS
a(n) is the number of ordered n-tuples of involutions on [n] that pairwise commute. Two involutions x,y on [n] commute if x*y = y*x.
LINKS
CROSSREFS
Main diagonal of A362824.
Cf. A362383, A362643, A362821, A362822 (isomorphism classes).
Sequence in context: A321604 A276124 A104166 * A368140 A273054 A065401
KEYWORD
nonn
AUTHOR
Andrew Howroyd, May 06 2023
STATUS
approved

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Last modified July 19 19:39 EDT 2024. Contains 374436 sequences. (Running on oeis4.)