%I #25 Jan 14 2022 23:19:34
%S 1,1,6,88,5136,1052154,706474926,1581054875274,12140605885784816,
%T 328173091958855376334,31831409045512513121561226,
%U 11234306828778006073392046869300,14576263867446651299709243211339018934,70075728362101598938266196294267261948879446
%N Number of unlabeled semi-strong digraphs on n nodes with pairwise different components.
%C Weigh transform of A035512. - _Andrew Howroyd_, Sep 10 2018
%C A digraph is semi-strong if all its weakly connected components are strongly connected. - _Andrew Howroyd_, Jan 14 2022
%H Andrew Howroyd, <a href="/A054952/b054952.txt">Table of n, a(n) for n = 1..50</a>
%H V. A. Liskovets, <a href="http://www.cs.uwaterloo.ca/journals/JIS/VOL3/LISK/Derseq.html">Some easily derivable sequences</a>, J. Integer Sequences, 3 (2000), #00.2.2.
%F G.f.: -1 + Product_{n > 0} (1 + x^n)^A035512(n). - _Andrew Howroyd_, Sep 10 2018
%t m = 15;
%t A035512 = Cases[Import["https://oeis.org/A035512/b035512.txt", "Table"], {_, _}][[All, 2]];
%t gf = -1 + Product[(1 + x^n)^A035512[[n + 1]], {n, 1, m}];
%t CoefficientList[gf + O[x]^m , x] // Rest (* _Jean-François Alcover_, Aug 26 2019, after _Andrew Howroyd_ *)
%Y Cf. A035512, A054951, A054953, A054954.
%K nonn,easy
%O 1,3
%A _N. J. A. Sloane_, May 24 2000
%E More terms from _Vladeta Jovovic_, Mar 11 2003
%E a(12)-a(14) from _Andrew Howroyd_, Sep 10 2018
|