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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.

A005412 Number of non-vanishing Feynman diagrams of order 2n for the vacuum polarization (the proper two-point function of the photon) and for the self-energy (the proper two-point function of the electron) in quantum electrodynamics (QED).

Table of values

n a(n)
1 1
2 3
3 18
4 153
5 1638
6 20898
7 307908
8 5134293
9 95518278
10 1961333838
11 44069970348
12 1075902476058
13 28367410077468
14 803551902237828
15 24342558819042888
16 785445178323709773
17 26896354975287884358
18 974297972094661642518
19 37225733779871789177628
20 1496237868417003741147438

List of values

[1, 3, 18, 153, 1638, 20898, 307908, 5134293, 95518278, 1961333838, 44069970348, 1075902476058, 28367410077468, 803551902237828, 24342558819042888, 785445178323709773, 26896354975287884358, 974297972094661642518, 37225733779871789177628, 1496237868417003741147438]

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

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