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 A098000 Number of outerplanar graphs on n labeled nodes. 5
 1, 1, 2, 8, 63, 893, 19714, 597510, 22903403, 1056115331, 56744710974, 3475626211316, 238818544070905, 18183183610029003, 1519020289266947462, 138117136134012654182, 13576724206357958780409, 1434561741418662640589225, 162136032834834405685977058, 19516966563322659948894106704 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS Andrew Howroyd, Table of n, a(n) for n = 0..200 M. Bodirsky and M. Kang, The asymptotic number of outerplanar graphs. S. R. Finch, Planar graph growth constants. Steven R. Finch, Planar graph growth constants [Cached copy, with permission of the author] FORMULA Recurrence known, see Bodirsky and Kang. Exponential transform of A097998. - Andrew Howroyd, Feb 12 2021 PROG (PARI) seq(n)={Vec(serlaplace(exp(intformal(serreverse(x/exp((1 + 5*x - sqrt(1 - 6*x + x^2 + O(x^n)))/8))/x))))} \\ Andrew Howroyd, Feb 12 2021 CROSSREFS Cf. A097998, A097999, A111564, A005470. Sequence in context: A153530 A153559 A193195 * A084279 A153526 A153554 Adjacent sequences:  A097997 A097998 A097999 * A098001 A098002 A098003 KEYWORD nonn AUTHOR Steven Finch, Sep 08 2004 EXTENSIONS a(0)=1 prepended and terms a(17) and beyond from Andrew Howroyd, Feb 12 2021 STATUS approved

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Last modified December 1 22:12 EST 2021. Contains 349435 sequences. (Running on oeis4.)