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.

A386421 Odd numbers k that are closer to being perfect than previous terms and also satisfy the condition that gcd(k, A003961(k)) is equal to gcd(sigma(k), A003961(k)), where A003961(n) is fully multiplicative with a(prime(k)) = prime(k+1), and sigma is the sum of divisors function.

Table of values

n a(n)
1 1
2 3
3 9
4 21
5 63
6 135
7 855
8 1485
9 25245
10 34155
11 43785
12 46035
13 1665825
14 1805475
15 22982505
16 125011845
17 127371195
18 657814575

List of values

[1, 3, 9, 21, 63, 135, 855, 1485, 25245, 34155, 43785, 46035, 1665825, 1805475, 22982505, 125011845, 127371195, 657814575]

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

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