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.

A089374 Numbers n such that the concatenation (in descending order) of all the divisors of n, with 1 in the least significant position, is prime (or 1).

Table of values

n a(n)
1 1
2 3
3 4
4 7
5 13
6 19
7 25
8 31
9 39
10 43
11 48
12 91
13 97
14 103
15 109
16 117
17 151
18 157
19 181
20 193
21 211
22 241
23 244
24 247
25 271
26 289
27 292
28 301
29 309
30 325
31 337
32 349
33 367
34 388
35 409
36 421
37 439
38 487
39 523
40 547
41 571
42 597
43 601
44 613
45 628
46 631
47 633
48 687
49 691
50 703
51 711
52 733
53 769
54 772
55 793
56 811

List of values

[1, 3, 4, 7, 13, 19, 25, 31, 39, 43, 48, 91, 97, 103, 109, 117, 151, 157, 181, 193, 211, 241, 244, 247, 271, 289, 292, 301, 309, 325, 337, 349, 367, 388, 409, 421, 439, 487, 523, 547, 571, 597, 601, 613, 628, 631, 633, 687, 691, 703, 711, 733, 769, 772, 793, 811]

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

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