A247180 - OEIS

A247180

Numbers with nonrepeating smallest prime factor.

2, 3, 5, 6, 7, 10, 11, 13, 14, 15, 17, 18, 19, 21, 22, 23, 26, 29, 30, 31, 33, 34, 35, 37, 38, 39, 41, 42, 43, 46, 47, 50, 51, 53, 54, 55, 57, 58, 59, 61, 62, 65, 66, 67, 69, 70, 71, 73, 74, 75, 77, 78, 79, 82, 83, 85, 86, 87, 89, 90, 91, 93, 94, 95, 97, 98

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Complement of the union of {1} and A283050. The asymptotic density of this sequence is 1 - A283071 = 0.6699019646... - Amiram Eldar, Dec 08 2020

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

FORMULA

a(n) mod A088377(a(n)) > 0;

A067029(a(n)) = 1.

MATHEMATICA

Select[Range[100], FactorInteger[#][[1, 2]]==1&] (* Harvey P. Dale, Jan 29 2020 *)