

A143841


Table read by antidiagonals: T(n,k) is the number of strongly connected directed multigraphs with loops with n arcs and k vertices.


1



1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 2, 1, 0, 1, 1, 2, 3, 1, 0, 1, 1, 2, 4, 7, 1, 0, 1, 1, 2, 4
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OFFSET

0,13


COMMENTS

Partial sums of the rows of A139622, i.e., T(n,k) = sum(T139622(n,p),p=0..k).
T(n,2) = T129620(n,2)  n(n1)/2.
If k>=n, T(n,k) = A139627(n).


LINKS

Table of n, a(n) for n=0..31.


CROSSREFS

Cf. A138107, A129620, A143842.
Sequence in context: A262553 A247506 A182172 * A276719 A276837 A269941
Adjacent sequences: A143838 A143839 A143840 * A143842 A143843 A143844


KEYWORD

nonn,tabl


AUTHOR

Benoit Jubin, Sep 02 2008


STATUS

approved



