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A288271 a(n) is the number of rooted maps with n edges and one face on an orientable surface of genus 4. 10

%I

%S 225225,12317877,351683046,7034538511,111159740692,1480593013900,

%T 17302190625720,182231849209410,1763184571730010,15894791312284170,

%U 134951136993773100,1088243826731751690,8391311316938069520,62210659883935683120,445441857820701181440,3092035882104030618900

%N a(n) is the number of rooted maps with n edges and one face on an orientable surface of genus 4.

%H Sean R. Carrell, Guillaume Chapuy, <a href="http://arxiv.org/abs/1402.6300">Simple recurrence formulas to count maps on orientable surfaces</a>, arXiv:1402.6300 [math.CO], 2014.

%F G.f.: -143*y*(y-1)^8*(1575*y^6 + 13689*y^5 + 4689*y^4 - 34417*y^3 + 11361*y^2 + 7017*y - 2339)/(y-2)^23, where y=A000108(x).

%t Q[0, 1, 0] = 1; Q[n_, f_, g_] /; n < 0 || f < 0 || g < 0 = 0;

%t Q[n_, f_, g_] := Q[n, f, g] = 6/(n+1)((2n-1)/3 Q[n-1, f, g] + (2n-1)/3 Q[n - 1, f-1, g] + (2n-3)(2n-2)(2n-1)/12 Q[n-2, f, g-1] + 1/2 Sum[l = n-k; Sum[v = f-u; Sum[j = g-i; Boole[l >= 1 && v >= 1 && j >= 0] (2k-1)(2l-1) Q[k-1, u, i] Q[l-1, v, j], {i, 0, g}], {u, 1, f}], {k, 1, n}]);

%t a[n_] := Q[n, 1, 4];

%t Table[a[n], {n, 8, 23}] (* _Jean-Fran├žois Alcover_, Oct 16 2018 *)

%o (PARI)

%o A000108_ser(N) = my(x='x+O('x^(N+1))); (1 - sqrt(1-4*x))/(2*x);

%o A288271_ser(N) = {

%o my(y = A000108_ser(N+1));

%o -143*y*(y-1)^8*(1575*y^6 + 13689*y^5 + 4689*y^4 - 34417*y^3 + 11361*y^2 + 7017*y - 2339)/(y-2)^23;

%o };

%o Vec(A288271_ser(16))

%Y Rooted maps of genus 4 with n edges and f faces for 1<=f<=10: this sequence, A288272 f=2, A288273 f=3, A288274 f=4, A288275 f=5, A288276 f=6, A288277 f=7, A288278 f=8, A288279 f=9, A288280 f=10.

%Y Column 1 of A269924.

%Y Cf. A000108.

%K nonn

%O 8,1

%A _Gheorghe Coserea_, Jun 08 2017

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Last modified January 26 01:48 EST 2020. Contains 331270 sequences. (Running on oeis4.)