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.

A129335 a(n) = phi(n!!) where phi is the Euler totient function. In other words, a(n) = A000010(A006882(n)).

Table of values

n a(n)
1 1
2 1
3 2
4 4
5 8
6 16
7 48
8 128
9 432
10 1024
11 4320
12 12288
13 51840
14 147456
15 777600
16 2359296
17 12441600
18 42467328
19 223948800
20 849346560
21 4702924800
22 16986931200
23 103464345600
24 407686348800
25 2586608640000
26 9784472371200
27 69838433280000

List of values

[1, 1, 2, 4, 8, 16, 48, 128, 432, 1024, 4320, 12288, 51840, 147456, 777600, 2359296, 12441600, 42467328, 223948800, 849346560, 4702924800, 16986931200, 103464345600, 407686348800, 2586608640000, 9784472371200, 69838433280000]

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

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