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 A140186 Number of connected groupoids (categories all of whose morphisms are invertible) with n more morphisms than objects. 2
 2, 1, 2, 2, 1, 2, 3, 5, 2, 2, 2, 5, 2, 2, 3, 15, 1, 5, 2, 5, 3, 2, 3, 15, 3, 2, 6, 4, 2, 4, 7, 51, 1, 4, 3, 14, 1, 2, 4, 14, 1, 6, 4, 4, 3, 3, 6, 52, 2, 5, 2, 7, 1, 15, 4, 13, 3, 2, 2, 13, 4, 2, 18, 267, 1, 4, 3, 5, 1, 9, 7, 50, 2, 2, 4, 4, 2, 6, 8, 52, 15, 2, 3, 15, 1, 2, 3, 14, 1, 10, 3, 5, 4 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS a(n) >= A000001(n+1) (number of groups of order n+1). LINKS FORMULA a(0) = 2 and if n>0, a(n) = sum(A000001((n+k)/(k^2)),k^2|n+k). (see formula for A140185) CROSSREFS Cf. A140185, A140187, A140188. Sequence in context: A132749 A271106 A273673 * A078498 A178522 A131240 Adjacent sequences:  A140183 A140184 A140185 * A140187 A140188 A140189 KEYWORD nonn AUTHOR Benoit Jubin, May 12 2008 STATUS approved

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Last modified December 10 23:29 EST 2019. Contains 329910 sequences. (Running on oeis4.)