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A060349

a(n) = n^(n+2)*(n^2 - 1)*(n+3)*(n+2)*(5*n - 7)/5760.

81, 5824, 328125, 16901136, 847425747, 42630905856, 2186213819427, 115293750000000, 6283133610195442, 354769407810994176, 20781472563720847342, 1263485180096661430272, 79727340621643066406250, 5219469342167970210643968, 354305349685394263423480746

(list; graph; refs; listen; history; text; internal format)

OFFSET

3,1

COMMENTS

For n >= 3, a(n) is the number of nonequivalent primitive meromorphic functions with one pole of order n on a Riemann surface of genus 2.

REFERENCES

B. Shapiro, M. Shapiro and A. Vainshtein, Ramified coverings of S^2 with one degenerate branching point and enumeration of edge-ordered graphs, Amer. Math. Soc. Transl., Vol. 180 (1997), pp. 219-227.

LINKS

Harry J. Smith, Table of n, a(n) for n = 3..200

MATHEMATICA

Table[(n^(n+2) (n^2-1)(n+3)(n+2)(5n-7))/5760, {n, 3, 20}] (* Harvey P. Dale, Jan 10 2013 *)

PROG

(PARI) { for (n=3, 200, write("b060349.txt", n, " ", n^(n + 2)*(n^2 - 1)*(n + 3)*(n + 2)*(5*n - 7)/5760); ) } \\ Harry J. Smith, Jul 04 2009

CROSSREFS

Cf. A007830, A060348.

Sequence in context: A260858 A237300 A237937 * A212706 A036354 A205887

Adjacent sequences: A060346 A060347 A060348 * A060350 A060351 A060352

KEYWORD

nonn

AUTHOR

Noam Katz (noamkj(AT)hotmail.com), Mar 30 2001

STATUS

approved