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.

A307794 a(1) = 1; a(n+1) = Sum_{d|n} sigma(d)*a(d), where sigma = sum of divisors (A000203).

Table of values

n a(n)
1 1
2 1
3 4
4 17
5 123
6 739
7 8888
8 71105
9 1066698
10 13867091
11 249608380
12 2995300561
13 83868424715
14 1174157946011
15 28179790775372
16 676314978609683
17 20965764337966871
18 377383758083403679
19 14717966565266619443
20 294359331305332388861
21 12363091914824209940661
22 395618941274374718172273

List of values

[1, 1, 4, 17, 123, 739, 8888, 71105, 1066698, 13867091, 249608380, 2995300561, 83868424715, 1174157946011, 28179790775372, 676314978609683, 20965764337966871, 377383758083403679, 14717966565266619443, 294359331305332388861, 12363091914824209940661, 395618941274374718172273]

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

Content is available under The OEIS End-User License Agreement.