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A319343
Filter sequence combining the prime signature of phi(d) from all proper divisors d of n.
4
1, 2, 2, 3, 2, 4, 2, 4, 5, 6, 2, 7, 2, 8, 9, 10, 2, 11, 2, 12, 13, 8, 2, 14, 15, 16, 13, 17, 2, 18, 2, 19, 13, 20, 21, 22, 2, 16, 23, 24, 2, 25, 2, 17, 26, 8, 2, 27, 28, 29, 30, 31, 2, 25, 21, 32, 23, 16, 2, 33, 2, 34, 35, 36, 37, 25, 2, 38, 13, 39, 2, 40, 2, 41, 42, 31, 43, 44, 2, 45, 46, 47, 2, 48, 49, 34, 23, 32, 2, 50, 51, 17, 52, 8, 37, 53, 2, 54, 35
OFFSET
1,2
COMMENTS
Restricted growth sequence transform of A319342.
LINKS
PROG
(PARI)
up_to = 65537;
A319342(n) = { my(m=1); fordiv(n, d, if((d<n), m *= prime(A318881(d)))); (m); }; \\ Needs also code from A318881
v319343 = rgs_transform(vector(up_to, n, A319342(n)));
A319343(n) = v319343[n];
CROSSREFS
Cf. also A305983.
Sequence in context: A353565 A318835 A319353 * A300827 A144371 A323157
KEYWORD
nonn
AUTHOR
Antti Karttunen, Sep 17 2018
STATUS
approved