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.

A217307 Minimal natural number (in decimal representation) with n prime substrings in base-7 representation (substrings with leading zeros are considered to be nonprime).

Table of values

n a(n)
0 1
1 2
2 16
3 17
4 115
5 121
6 509
7 821
8 3251
9 4721
10 5749
11 22760
12 25301
13 41673
14 142950
15 173819
16 291714
17 920561
18 1222716
19 2041709
20 4450031
21 8559017
22 9350687
23 14295199
24 31150219
25 50568439
26 71502954
27 100066398
28 218051538
29 353979075
30 500526787
31 702815371
32 1512442643

List of values

[1, 2, 16, 17, 115, 121, 509, 821, 3251, 4721, 5749, 22760, 25301, 41673, 142950, 173819, 291714, 920561, 1222716, 2041709, 4450031, 8559017, 9350687, 14295199, 31150219, 50568439, 71502954, 100066398, 218051538, 353979075, 500526787, 702815371, 1512442643]

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

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