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A392613
Numbers k such that A392858(k) divides k.
3
0, 1, 2, 3, 4, 6, 10, 12, 18, 24, 30, 42, 60, 90, 120, 150, 180, 210, 220, 330, 420, 630, 840, 1050, 1260, 1470, 1680, 1890, 2100, 2310, 2314, 2340, 2730, 4620, 6930, 9240, 11550, 13860, 16170, 18480, 20790, 23100, 25410, 27720, 30030, 30090, 32130, 39270, 60060, 60690, 90090, 120120, 150150, 180180, 210210, 240240
OFFSET
1,3
FORMULA
{k such that k is a multiple of A028234(A276086(k))}.
EXAMPLE
A392858(0) = 1 and 0 is also a multiple of 1, therefore 0 is included as the first term of this sequence.
A276086(220) = 495 = 3^2 * 5^1 * 11^1. Removing the least prime factor in toto leaves just 5*11, which divides 220 = 2^2 * 5^1 * 11^1, therefore 220 is included.
PROG
(PARI)
A392858(n) = { my(m=1, p=2, e=0); while(n, if(n%p, if(e, m *= p^(n%p), e++)); n = n\p; p = nextprime(1+p)); (m); };
is_A392613(k) = !(k % A392858(k));
CROSSREFS
Subsequence of A392612.
Subsequences: A002110, A060735.
Cf. also A328387, A351226.
Sequence in context: A330006 A288784 A322164 * A237823 A395617 A241547
KEYWORD
nonn,base
AUTHOR
Antti Karttunen, Jan 25 2026
STATUS
approved