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.

A031439 a(0) = 1, a(n) is the greatest prime factor of a(n-1)^2+1 for n > 0.

Table of values

n a(n)
0 1
1 2
2 5
3 13
4 17
5 29
6 421
7 401
8 53
9 281
10 3037
11 70949
12 1713329
13 1467748131121
14 37142837524296348426149
15 101591133424866642486477019709
16 1650979973845742266714536305651329
17 78343914631785958284737
18 4029445531112797145738746391569
19 350080544438648120162733678636001
20 26208090024628793745288451837610346882122253572537
21 4717815978577117335515270825550279551117660519482308365269206484133871485221

List of values

[1, 2, 5, 13, 17, 29, 421, 401, 53, 281, 3037, 70949, 1713329, 1467748131121, 37142837524296348426149, 101591133424866642486477019709, 1650979973845742266714536305651329, 78343914631785958284737, 4029445531112797145738746391569, 350080544438648120162733678636001, 26208090024628793745288451837610346882122253572537, 4717815978577117335515270825550279551117660519482308365269206484133871485221]

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

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