cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A321705 Number of genus 5 rooted hypermaps with n darts.

Original entry on oeis.org

604800, 57170880, 2936606400, 108502598960, 3225186125460, 81861294718764, 1840409325096500, 37558997857897164, 708015469597497732, 12488421105878928700, 208161512148250424484, 3304395638081490531324, 50267199680265668419244, 736516493829967530909204, 10437808798822929984593100
Offset: 11

Views

Author

Gheorghe Coserea, Nov 17 2018

Keywords

Crossrefs

Column 5 of A321710.

Programs

  • PARI
    seq(N) = {
      my(x='x+O('x^(N+2)), y=(1-sqrt(1-8*x))/(4*x));
      Vec(y*(y - 1)^11*(13150*y^19 - 315600*y^18 + 6947865*y^17 - 70489470*y^16 + 569637816*y^15 - 3253135788*y^14 + 14658702716*y^13 - 51696766668*y^12 + 146255446788*y^11 - 332779761068*y^10 + 610739916966*y^9 - 900544355928*y^8 + 1057440629016*y^7 - 973453624356*y^6 + 685359139356*y^5 - 355019010868*y^4 + 127180243662*y^3 - 28342783668*y^2 + 3224985513*y - 120590634)/(4*(y - 2)^22*(y + 1)^17));
    };
    seq(15)

Formula

G.f.: y*(y - 1)^11*(13150*y^19 - 315600*y^18 + 6947865*y^17 - 70489470*y^16 + 569637816*y^15 - 3253135788*y^14 + 14658702716*y^13 - 51696766668*y^12 + 146255446788*y^11 - 332779761068*y^10 + 610739916966*y^9 - 900544355928*y^8 + 1057440629016*y^7 - 973453624356*y^6 + 685359139356*y^5 - 355019010868*y^4 + 127180243662*y^3 - 28342783668*y^2 + 3224985513*y - 120590634)/(4*(y - 2)^22*(y + 1)^17), where y=A000108(2*x).