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.

A293309 Number of magic labelings of the graph LOOP X C_10 (see comments) having magic sum n, n >= 0.

Original entry on oeis.org

1, 123, 3281, 39175, 286555, 1508401, 6271378, 21836366, 66220705, 179784715, 445824731, 1025102013, 2211041131, 4514532465, 8789910980, 16416797116, 29556115153, 51502789451, 87162399205, 143684487475, 231291309931, 364347612673, 562724586326
Offset: 0

Views

Author

L. Edson Jeffery, Oct 05 2017

Keywords

Comments

The graph LOOP X C_n is constructed by attaching a loop to each vertex of the cycle graph C_n.
The generating function for this sequence was found via the "Omega" package for Mathematica authored by Axel Riese. The package can be downloaded from the link given in the article by G. E. Andrews et al.

Crossrefs

Cf. A000027, A000217, A019298, A006325, A244497, A244879, A244873, A244880, A293310 (magic labelings of LOOP X C_k, for k=1..9).

Programs

  • Mathematica
    CoefficientList[Series[(1 + 112*z + 1983*z^2 + 9684*z^3 + 16120*z^4 + 9684*z^5 + 1983*z^6 + 112*z^7 + z^8)/(1 - z)^11, {z, 0, 22}], z]
    LinearRecurrence[{11, -55, 165, -330, 462, -462, 330, -165, 55, -11, 1}, {1, 123, 3281, 39175, 286555, 1508401, 6271378, 21836366, 66220705, 179784715, 445824731}, 25] (* Vincenzo Librandi, Oct 12 2017 *)

Formula

G.f.: (1 + 112*z + 1983*z^2 + 9684*z^3 + 16120*z^4 + 9684*z^5 + 1983*z^6 + 112*z^7 + z^8)/(1 - z)^11.