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.

A290051 Least k > 1 such that the set of distinct prime divisors of k is equal to the set of distinct prime divisors of sigma_n(k) where sigma_n (k) is result of applying sum-of-divisors function n times to k.

Table of values

n a(n)
1 6
2 2
3 294
4 2
5 126
6 112
7 310
8 14
9 150
10 840
11 3200
12 98
13 45360
14 10500
15 57120
16 40320
17 242250
18 9548
19 21839790
20 3756480
21 200425680
22 678810
23 1359540

List of values

[6, 2, 294, 2, 126, 112, 310, 14, 150, 840, 3200, 98, 45360, 10500, 57120, 40320, 242250, 9548, 21839790, 3756480, 200425680, 678810, 1359540]

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

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