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A326141
Odd numbers n for which A318879(n) is not zero and A318879(n) divides A318878(n); odd numbers such that A326140(n) = A318879(n).
5
105, 195, 4785, 22515, 56865, 228285, 237315, 484245, 671853, 1838145, 1946955, 3446895, 4522695, 12955245, 37730865, 52475055, 53568885, 87612975
OFFSET
1,1
COMMENTS
Not a subsequence of A036798, even though many terms are members.
Questions: Are all terms multiples of three? Multiples of 3^(2k+1) but not of 3^(2k)? Are any of the terms included in A228058, A326137?
PROG
(PARI) isA326141(n) = if(!(n%2), 0, my(t=0, u=0); fordiv(n, d, d -= 2*eulerphi(d); if(d<0, t -= d, u += d)); (gcd(t, u)==u));
KEYWORD
nonn,more
AUTHOR
Antti Karttunen, Jun 09 2019
STATUS
approved