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A125698 Number of connected categories with n morphisms. 2
1, 2, 8, 41, 258, 2407 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Connected in the sense that if the morphism direction and composition is ignored, resulting in a multigraph, that multigraph is connected.

Inverse Euler transform of A125696.

LINKS

Table of n, a(n) for n=1..6.

Eric Weisstein's World of Mathematics, Category

EXAMPLE

The 8 categories with 3 morphisms consist of 7 3-element monoids and one 2-object category with a single morphism between the objects.

CROSSREFS

Cf. A125696, A125699, A125700.

Sequence in context: A099240 A134055 A136281 * A231495 A052447 A226458

Adjacent sequences:  A125695 A125696 A125697 * A125699 A125700 A125701

KEYWORD

hard,more,nonn

AUTHOR

Franklin T. Adams-Watters and Christian G. Bower, Jan 05 2007

STATUS

approved

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Last modified September 20 12:42 EDT 2018. Contains 315239 sequences. (Running on oeis4.)