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A238357 Number of genus-7 rooted maps with n edges. 14
14230536445125, 3128879373858000, 360626952084151500, 29001816720933903504, 1828003659229082834100, 96187365300257285300064, 4395215998078319892167640, 179153431308203084149883760, 6641365771586560905099092466, 227189907562197156785567456832, 7252879937219595844346639732688 (list; graph; refs; listen; history; text; internal format)
OFFSET

14,1

LINKS

Table of n, a(n) for n=14..24.

Sean R. Carrell, Guillaume Chapuy, Simple recurrence formulas to count maps on orientable surfaces, arXiv:1402.6300 [math.CO], (19-March-2014)

Gheorghe Coserea, The g.f. as a rational function of y=A005159(x)

MATHEMATICA

T[0, 0] = 1; T[n_, g_] /; g < 0 || g > n/2 = 0; T[n_, g_] := T[n, g] = ((4 n - 2)/3 T[n - 1, g] + (2 n - 3) (2 n - 2) (2 n - 1)/12 T[n - 2, g - 1] + 1/2 Sum[(2 k - 1) (2 (n - k) - 1) T[k - 1, i] T[n - k - 1, g - i], {k, 1, n - 1}, {i, 0, g}])/((n + 1)/6);

a[n_] := T[n, 7];

Table[a[n], {n, 14, 30}] (* Jean-Fran├žois Alcover, Jul 20 2018 *)

PROG

(PARI) \\ see A238396

(PARI)

system("wget http://oeis.org/A238357/a238357.txt");

A005159_ser(N) = my(x='x+O('x^(N+1))); (1 - sqrt(1-12*x))/(6*x);

A238357_ser(N) = subst(read("a238357.txt"), 'y, A005159_ser(N+14));

Vec(A238357_ser(11)) \\ Gheorghe Coserea, Jun 03 2017

CROSSREFS

Rooted maps with n edges of genus g for 0 <= g <= 10: A000168, A006300, A006301, A104742, A215402, A238355, A238356, this sequence, A238358, A238359, A238360.

Sequence in context: A172719 A226954 A068747 * A160935 A159271 A288277

Adjacent sequences:  A238354 A238355 A238356 * A238358 A238359 A238360

KEYWORD

nonn

AUTHOR

Joerg Arndt, Feb 26 2014

STATUS

approved

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Last modified August 3 18:51 EDT 2020. Contains 336201 sequences. (Running on oeis4.)