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.

A225172 Largest number which requires n iterations of the unitary totient function (A047994) to reach 1.

Table of values

n a(n)
0 1
1 2
2 6
3 14
4 42
5 86
6 186
7 462
8 930
9 1986
10 4170
11 6510
12 14682
13 29366
14 50342
15 73410
16 189498
17 287654
18 491190
19 849570
20 1699142
21 2433878
22 4280774
23 7978218
24 14442690
25 25900142
26 44400390
27 78492954
28 123958794
29 228018066
30 355388970
31 629582370
32 780686294

List of values

[1, 2, 6, 14, 42, 86, 186, 462, 930, 1986, 4170, 6510, 14682, 29366, 50342, 73410, 189498, 287654, 491190, 849570, 1699142, 2433878, 4280774, 7978218, 14442690, 25900142, 44400390, 78492954, 123958794, 228018066, 355388970, 629582370, 780686294]

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

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