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.

A237913 Smallest number m > 1 (not ending in a 0) such that m and the digit reversal of m have n prime factors (counted with multiplicity). Palindromes are included.

Table of values

n a(n)
1 2
2 4
3 8
4 88
5 252
6 2576
7 21708
8 2112
9 4224
10 8448
11 44544
12 48384
13 2977792
14 21989376
15 405504
16 4091904
17 441606144
18 405909504
19 886898688
20 677707776
21 4285005824
22 276486684672
23 21128282112
24 633498894336
25 2701312131072
26 6739855589376
27 29142024192
28 65892155129856
29 4815463645184
30 445488555884544

List of values

[2, 4, 8, 88, 252, 2576, 21708, 2112, 4224, 8448, 44544, 48384, 2977792, 21989376, 405504, 4091904, 441606144, 405909504, 886898688, 677707776, 4285005824, 276486684672, 21128282112, 633498894336, 2701312131072, 6739855589376, 29142024192, 65892155129856, 4815463645184, 445488555884544]

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

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