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 A192517 Table read by antidiagonals: T(n,k) = number of multigraphs with n vertices and k edges, with no loops allowed (n >= 1, k >= 0). 6
 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 2, 1, 0, 1, 1, 3, 3, 1, 0, 1, 1, 3, 6, 4, 1, 0, 1, 1, 3, 7, 11, 5, 1, 0, 1, 1, 3, 8, 17, 18, 7, 1, 0, 1, 1, 3, 8, 21, 35, 32, 8, 1, 0, 1, 1, 3, 8, 22, 52, 76, 48, 10, 1, 0, 1, 1, 3, 8, 23, 60, 132, 149, 75, 12, 1, 0 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,13 COMMENTS Rows converge to sequence A050535, i.e. T(n,k) = A050535(k) for n >= 2k. REFERENCES F. Harary and E. M. Palmer, Graphical Enumeration, Academic Press, NY, 1973, p. 171. LINKS Andrew Howroyd, Table of n, a(n) for n = 1..1275 (terms 1..78 from Alberto Tacchella computed using nauty 2.4, terms 79..595 from Sean A. Irvine computed using cycle index method of Harary and Palmer). R. J. Mathar, Statistics on Small Graphs, arXiv:1709.09000 [math.CO] (2017), Table 69. EXAMPLE Table begins: [1,0,0,0,0,0,0,0,0,...], [1,1,1,1,1,1,1,1,1,...], [1,1,2,3,4,5,7,8,10,...], [1,1,3,6,11,18,32,48,75,...], [1,1,3,7,17,35,76,149,291,...], [1,1,3,8,21,52,132,313,741,...], [1,1,3,8,22,60,173,471,1303,...], [1,1,3,8,23,64,197,588,1806,...], ... PROG (PARI) \\ See A191646 for G function. R(n)={Mat(vectorv(n, k, concat([1], G(k, n-1))))} { my(A=R(10)); for(n=1, #A, for(k=1, #A, print1(A[n, k], ", ")); print) } \\ Andrew Howroyd, May 14 2018 CROSSREFS Cf. A008406, A191646, A003082 (row 4), A014395 (row 5), A014396 (row 6). Sequence in context: A133607 A103631 A263191 * A309896 A083856 A081718 Adjacent sequences:  A192514 A192515 A192516 * A192518 A192519 A192520 KEYWORD nonn,tabl AUTHOR Alberto Tacchella, Jul 03 2011 STATUS approved

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Last modified January 23 19:34 EST 2020. Contains 331175 sequences. (Running on oeis4.)