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A054952 Number of labeled semi-strong digraphs on n nodes with pairwise different components. 3
1, 1, 6, 88, 5136, 1052154, 706474926, 1581054875274, 12140605885784816, 328173091958855376334, 31831409045512513121561226, 11234306828778006073392046869300, 14576263867446651299709243211339018934, 70075728362101598938266196294267261948879446 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Weigh transform of A035512. - Andrew Howroyd, Sep 10 2018

LINKS

Table of n, a(n) for n=1..14.

V. A. Liskovets, Some easily derivable sequences, J. Integer Sequences, 3 (2000), #00.2.2.

FORMULA

G.f.: -1 + Product_{n > 0} (1 + x^n)^A035512(n). - Andrew Howroyd, Sep 10 2018

MATHEMATICA

m = 15;

A035512 = Cases[Import["https://oeis.org/A035512/b035512.txt", "Table"], {_, _}][[All, 2]];

gf = -1 + Product[(1 + x^n)^A035512[[n + 1]], {n, 1, m}];

CoefficientList[gf + O[x]^m , x] // Rest (* Jean-Fran├žois Alcover, Aug 26 2019, after Andrew Howroyd *)

CROSSREFS

Cf. A035512, A054951, A054953, A054954.

Sequence in context: A327645 A309165 A127183 * A101148 A100297 A177568

Adjacent sequences:  A054949 A054950 A054951 * A054953 A054954 A054955

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, May 24 2000

EXTENSIONS

More terms from Vladeta Jovovic, Mar 11 2003

a(12)-a(14) from Andrew Howroyd, Sep 10 2018

STATUS

approved

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Last modified April 3 22:48 EDT 2020. Contains 333207 sequences. (Running on oeis4.)