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 A055349 Triangle of labeled mobiles (circular rooted trees) with n nodes and k leaves. 11
 1, 2, 0, 6, 3, 0, 24, 36, 8, 0, 120, 360, 220, 30, 0, 720, 3600, 4200, 1500, 144, 0, 5040, 37800, 71400, 47250, 11508, 840, 0, 40320, 423360, 1176000, 1234800, 545664, 98784, 5760, 0, 362880, 5080320, 19474560, 29635200, 20469456, 6618528 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Andrew Howroyd, Table of n, a(n) for n = 1..1275 (first 50 rows) FORMULA E.g.f. satisfies A(x, y)=xy-x*log(1-A(x, y))-x. EXAMPLE Triangle begins:      1;      2,     0;      6,     3,     0;     24,    36,     8,     0;    120,   360,   220,    30,     0;    720,  3600,  4200,  1500,   144,   0;   5040, 37800, 71400, 47250, 11508, 840, 0;   ... PROG (PARI) A(n)={my(v=Vec(serlaplace(serreverse(x/(y - log(1-x + O(x^n))))))); vector(#v, i, Vecrev(v[i]/y, i))} { my(T=A(10)); for(i=1, #T, print(T[i])) } \\ Andrew Howroyd, Sep 23 2018 CROSSREFS Row sums give A038037. Columns 1..8 are A000142, A055303, A055350, A055351, A055352, A055353, A055354, A055355. Cf. A055340, A055356, A055363. Sequence in context: A095834 A106828 A055302 * A161174 A291240 A233207 Adjacent sequences:  A055346 A055347 A055348 * A055350 A055351 A055352 KEYWORD nonn,tabl,eigen AUTHOR Christian G. Bower, May 15 2000 STATUS approved

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Last modified April 20 22:22 EDT 2019. Contains 322310 sequences. (Running on oeis4.)