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.

A136358 Increasing sequence obtained by union of two sequences {b(n)} and {c(n)}, where b(n) is the smallest odd composite number m such that both m-2 and m+2 are prime and the set of distinct prime factors of m consists of the first n odd primes and c(n) is the smallest composite number m such that both m-1 and m+1 are primes and the set of the distinct prime factors of m consists of the first n primes.

Table of values

n a(n)
1 4
2 6
3 9
4 15
5 30
6 105
7 420
8 2310
9 3465
10 15015
11 180180
12 765765
13 4084080
14 106696590
15 247342095
16 892371480
17 3011753745
18 9704539845
19 100280245065
20 103515091680
21 4412330782860
22 29682952539240
23 634473110526255
24 22514519501013540

List of values

[4, 6, 9, 15, 30, 105, 420, 2310, 3465, 15015, 180180, 765765, 4084080, 106696590, 247342095, 892371480, 3011753745, 9704539845, 100280245065, 103515091680, 4412330782860, 29682952539240, 634473110526255, 22514519501013540]

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

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