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.

A131905 Integers x such that sigma_2(k)=sigma_2(x) for some 0 where A001157=sigma_2 is the sum of squares of divisors.

Table of values

n a(n)
1 7
2 26
3 35
4 47
5 77
6 91
7 119
8 130
9 133
10 141
11 157
12 161
13 175
14 182
15 203
16 215
17 217
18 249
19 259
20 282
21 286
22 287
23 301
24 329
25 371
26 385
27 413
28 423
29 427
30 434
31 442
32 455
33 469
34 471
35 494
36 497
37 511
38 517
39 553
40 581
41 595
42 598
43 611
44 623
45 650
46 651
47 665
48 679
49 707
50 721
51 749
52 754
53 763
54 785

List of values

[7, 26, 35, 47, 77, 91, 119, 130, 133, 141, 157, 161, 175, 182, 203, 215, 217, 249, 259, 282, 286, 287, 301, 329, 371, 385, 413, 423, 427, 434, 442, 455, 469, 471, 494, 497, 511, 517, 553, 581, 595, 598, 611, 623, 650, 651, 665, 679, 707, 721, 749, 754, 763, 785]

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

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