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A038021 Triangle: T(n,k), k<=n: commutative groupoids with n elements and k idempotents. 3
1, 0, 1, 1, 2, 1, 38, 57, 27, 7, 13872, 18544, 9280, 2080, 192, 83360520, 104208775, 52110500, 13035000, 1632750, 82355 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
0,5
LINKS
CROSSREFS
Sequence in context: A127608 A038022 A173838 * A127609 A228860 A271204
KEYWORD
nonn,tabl,more
AUTHOR
Christian G. Bower, May 15 1998
STATUS
approved

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Last modified June 8 05:45 EDT 2024. Contains 373207 sequences. (Running on oeis4.)