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A030253 Number of nonisomorphic groupoids with 1 idempotent. 2
1, 4, 1485, 75503872, 1017252851596875, 5757133327963849592814528, 20215881652044379995902152075055222830, 61135717735233219050448568789931104340315383312314368 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

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

Index entries for sequences related to groupoids

CROSSREFS

Sequence in context: A160088 A094546 A203035 * A278549 A229664 A265661

Adjacent sequences:  A030250 A030251 A030252 * A030254 A030255 A030256

KEYWORD

nonn

AUTHOR

Christian G. Bower, Feb 15 1998 and May 15 1998

STATUS

approved

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Last modified December 6 22:42 EST 2021. Contains 349567 sequences. (Running on oeis4.)