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.

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A114289 Number of combinatorial types of n-dimensional polytopes with n+3 vertices.

Original entry on oeis.org

0, 1, 7, 31, 116, 379, 1133, 3210, 8803, 23701, 63239, 168287, 447905, 1194814, 3196180, 8576505, 23081668, 62292381, 168536249, 457035453, 1241954405, 3381289332, 9221603416, 25189382006, 68906572413, 188750887991
Offset: 1

Views

Author

Éric Fusy (eric.fusy(AT)inria.fr), Nov 21 2005

Keywords

References

  • B. Grünbaum, Convex Polytopes, Springer-Verlag, 2003, Second edition prepared by V. Kaibel, V. Klee and G. M. Ziegler, p. 121a.

Crossrefs

Programs

  • Maple
    N:=60: with(numtheory): G:=-ln(1-2*x^3/(1-2*x)^2): H:=-ln(1-2*x)+ln(1-x): K:=-1/2*x*(x-8*x^3-1+5*x^2-7*x^4+2*x^6+5*x^8-9*x^7+19*x^5-14*x^9+x^10+19*x^11-5*x^12+4*x^14-8*x^13)/(1-x)^5/(2*x^6-4*x^4+4*x^2-1)/(x+1)^2: series(1/(x^3-x^4)*(1/4*sum(phi(2*r+1)/(2*r+1)*subs(x=x^(2*r+1),G),r=0..N)+1/2*sum(phi(r)/r*subs(x=x^r,H),r=1..N)+K),x,N);
  • Mathematica
    terms = 26;
    G[x_] = -Log[1 - 2(x^3/(1 - 2x)^2)];
    H[x_] = -Log[1 - 2x] + Log[1 - x];
    K[x_] = -1/2 x (x - 8x^3 - 1 + 5x^2 - 7x^4 + 2x^6 + 5x^8 - 9x^7 + 19x^5 - 14x^9 + x^10 + 19x^11 - 5x^12 + 4x^14 - 8x^13)/(1-x)^5/(2x^6 - 4x^4 + 4x^2 - 1)/(x+1)^2;
    1/(x^3 - x^4) (1/4 Sum[EulerPhi[2r + 1]/(2r + 1) G[x^(2r + 1)], {r, 0, terms+2}] + 1/2 Sum[EulerPhi[r]/r H[x^r], {r, 1, terms+2}] + K[x]) + O[x]^(terms+2) // CoefficientList[#, x]& // Rest // Most // Round (* Jean-François Alcover, Dec 14 2018 *)

A114291 Number of combinatorial types of achiral n-dimensional polytopes with n+3 vertices, where a polytope is achiral if one of its geometric realizations has a reflection-symmetry.

Original entry on oeis.org

0, 1, 7, 24, 62, 141, 287, 561, 1035, 1886, 3319, 5838, 10030, 17323, 29395, 50291, 84795, 144374, 242641, 412126, 691522, 1173151, 1966929, 3334931, 5589311, 9474106, 15875699, 26906538, 45083426, 76404103, 128014623, 216944163
Offset: 1

Views

Author

Éric Fusy (eric.fusy(AT)inria.fr), Nov 21 2005

Keywords

References

  • B. Grünbaum, Convex Polytopes, Springer-Verlag, 2003, Second edition prepared by V. Kaibel, V. Klee and G. M. Ziegler, p. 121a.

Crossrefs

Programs

  • Mathematica
    LinearRecurrence[{2, 6, -14, -12, 38, 8, -54, 5, 44, -12, -20, 8, 4, -2}, {0, 1, 7, 24, 62, 141, 287, 561, 1035, 1886, 3319, 5838, 10030, 17323}, 32] (* Jean-François Alcover, Dec 14 2018 *)
  • PARI
    concat(0, Vec((2*x^11+4*x^10-2*x^9-15*x^8-5*x^7+23*x^6+15*x^5 -17*x^4-14*x^3+4*x^2 +5*x+1)*x^2/ (-1+x)^5/(2*x^6-4*x^4+4*x^2-1)/(x+1)^3 + O(x^50))) \\ Michel Marcus, Dec 12 2014

Formula

G.f.: (2*x^11+4*x^10-2*x^9-15*x^8-5*x^7+23*x^6+15*x^5-17*x^4 -14*x^3 +4*x^2+5*x+1) *x^2 / ((-1+x)^5*(2*x^6-4*x^4+4*x^2-1)*(x+1)^3).
Showing 1-2 of 2 results.