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.

A069619 a(1) = 7; a(2n) = smallest prime that is a right concatenation of a(2n-1) and a number with no insignificant zeros and a(2n+1) = smallest prime ending in ( the least significant digits) a(2n-1). Alternate left and right concatenation yielding primes.

Table of values

n a(n)
1 7
2 71
3 271
4 2711
5 52711
6 5271121
7 135271121
8 1352711219
9 271352711219
10 27135271121911
11 1227135271121911
12 122713527112191161
13 20122713527112191161
14 20122713527112191161109
15 2720122713527112191161109

List of values

[7, 71, 271, 2711, 52711, 5271121, 135271121, 1352711219, 271352711219, 27135271121911, 1227135271121911, 122713527112191161, 20122713527112191161, 20122713527112191161109, 2720122713527112191161109]

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

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