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.

A121407 Number of double eliminations of twin prime candidates within primorial intervals of p(n)#. That is, it is the number of twin prime candidates for which each half of the pair is composite, where one of those composites has p(n) for its lowest prime factor and the other composite has a prime less than p(n) for its lowest prime factor.

Table of values

n a(n)
1 0
2 0
3 0
4 2
5 18
6 210
7 2790
8 47610
9 901530
10 20591010
11 592452630
12 18202996350
13 667760974650
14 27146297697750
15 1157142993063750
16 53925515761020750
17 2835489033177050250
18 166057836818071448250
19 10054640164031031318750

List of values

[0, 0, 0, 2, 18, 210, 2790, 47610, 901530, 20591010, 592452630, 18202996350, 667760974650, 27146297697750, 1157142993063750, 53925515761020750, 2835489033177050250, 166057836818071448250, 10054640164031031318750]

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

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