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A324349 a(n) = A324122(A005940(1+n)), where A005940 is the Doudna sequence and A324122(n) = sigma(n) - gcd(n*d(n), sigma(n)). 5
0, 2, 2, 6, 4, 0, 12, 14, 6, 16, 12, 24, 30, 36, 36, 30, 10, 16, 28, 36, 44, 48, 72, 48, 54, 90, 122, 90, 152, 96, 120, 60, 12, 32, 36, 0, 68, 48, 102, 80, 92, 128, 168, 144, 246, 216, 120, 120, 132, 168, 222, 216, 336, 360, 402, 192, 396, 464, 600, 272, 780, 360, 362, 126, 16, 40, 52, 72, 80, 96, 150, 112, 84, 208, 264, 112, 366, 288, 312, 184, 164, 272, 360, 0, 568 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
Zeros occur in the same positions as in A324057, and can be obtained by sorting into ascending order the terms obtained with A156552(A001599(n)), n >= 1.
LINKS
FORMULA
a(n) = A324122(A005940(1+n)).
a(n) = A324054(n) - A324058(n).
For n > 0, a(n) = A324189(A054429(n)).
PROG
(PARI)
A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); t }; \\ From A005940
A324122(n) = (sigma(n) - gcd(sigma(n), n*numdiv(n)));
A324349(n) = A324122(A005940(1+n));
CROSSREFS
Cf. also A001599.
Sequence in context: A276085 A334870 A324122 * A092384 A061915 A366898
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 24 2019
STATUS
approved

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Last modified March 29 04:59 EDT 2024. Contains 371264 sequences. (Running on oeis4.)