OFFSET
1,1
COMMENTS
Numbers that have one even prime factor (2) and an odd number of odd prime factors with multiplicity.
Numbers that have an even number of prime factors with multiplicity and whose arithmetic derivative (A003415) is odd.
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..10000
FORMULA
a(n) = 2*A067019(n).
PROG
(PARI) \\ See A369965
CROSSREFS
Cf. A369661 (numbers whose arithmetic derivative is in this sequence).
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 08 2024
STATUS
approved