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MATHEMATICA
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Q[0, 1, 0] = 1; Q[n_, f_, g_] /; n < 0 || f < 0 || g < 0 = 0;
Q[n_, f_, g_] := Q[n, f, g] = 6/(n + 1) ((2 n - 1)/3 Q[n - 1, f, g] + (2 n - 1)/3 Q[n - 1, f - 1, g] + (2 n - 3) (2 n - 2) (2 n - 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] (2 k - 1) (2 l - 1) Q[k - 1, u, i] Q[l - 1, v, j], {i, 0, g}], {u, 1, f}], {k, 1, n}]);
a[n_] := Q[n, 7, 1];
Table[a[n], {n, 8, 24}] (* Jean-François Alcover, Oct 18 2018 *)
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CROSSREFS
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Rooted maps of genus 1 with n edges and f faces for 1<=f<=10: A002802(with offset 2) f=1, A006295 f=2, A006296 f=3, A288071 f=4, A288072 f=5, A287046 f=6, this sequence, A287048 f=8, A288073 f=9, A288074 f=10.
Column 7 of A269921, column 1 of A270411.
Cf. A000108.
Sequence in context: A106774 A189985 A338606 * A075671 A186556 A205983
Adjacent sequences: A287044 A287045 A287046 * A287048 A287049 A287050
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