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.

A100986 Smallest k such that concatenation of r*k and 1 is a prime for all r = 1 to n but not prime for r = n+1, or smallest k such that 10*r*k+1 is a prime for all r = 1 to n but not prime for r = n+1.

Table of values

n a(n)
1 1
2 3
3 21
4 33
5 1083
6 2541
7 822486
8 51282
9 1296060612

List of values

[1, 3, 21, 33, 1083, 2541, 822486, 51282, 1296060612]

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

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