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.

A167872 A sequence of moments connected with Feynman numbers (A000698): Half the number of Feynman diagrams of order 2(n+1), for the electron self-energy in quantum electrodynamics (QED), i.e., all proper diagrams including Furry vanishing diagrams (those that vanish in 4-dimensional QED because of Furry theorem).

Table of values

n a(n)
0 1
1 3
2 21
3 207
4 2529
5 36243
6 591381
7 10786527
8 217179009
9 4782674403
10 114370025301
11 2952426526767
12 81864375589089
13 2427523337157363
14 76683680366193621
15 2571609710380950207
16 91265370849151405569
17 3417956847888948899523

List of values

[1, 3, 21, 207, 2529, 36243, 591381, 10786527, 217179009, 4782674403, 114370025301, 2952426526767, 81864375589089, 2427523337157363, 76683680366193621, 2571609710380950207, 91265370849151405569, 3417956847888948899523]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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