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.

A258660 Numbers n such that the number of digits d in n is not prime and for each factor f of d the sum of the d/f digit groupings of size f is a square.

Table of values

n a(n)
1 1
2 4
3 9
4 1521
5 3600
6 7396
7 8100
8 103041
9 120409
10 160801
11 11471769
12 11655396
13 12802084
14 15210000
15 22724289
16 36000000
17 42889401
18 42928704
19 45481536
20 45968400
21 46009089
22 54567769
23 61811044
24 62236321
25 70006689
26 73925604
27 73960000
28 76965529
29 79174404
30 81000000
31 85008400
32 97693456
33 97713225
34 100000000

List of values

[1, 4, 9, 1521, 3600, 7396, 8100, 103041, 120409, 160801, 11471769, 11655396, 12802084, 15210000, 22724289, 36000000, 42889401, 42928704, 45481536, 45968400, 46009089, 54567769, 61811044, 62236321, 70006689, 73925604, 73960000, 76965529, 79174404, 81000000, 85008400, 97693456, 97713225, 100000000]

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

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