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A349138
Inverse Möbius transform of A349137, where A349137(n) = phi(A003602(n)).
3
1, 2, 2, 3, 3, 4, 3, 4, 6, 6, 3, 6, 7, 6, 8, 5, 7, 12, 5, 9, 14, 6, 5, 8, 15, 14, 12, 9, 9, 16, 9, 6, 20, 14, 11, 18, 19, 10, 16, 12, 13, 28, 11, 9, 34, 10, 9, 10, 23, 30, 20, 21, 19, 24, 17, 12, 34, 18, 9, 24, 31, 18, 34, 7, 29, 40, 17, 21, 30, 22, 13, 24, 37, 38, 38, 15, 29, 32, 17, 15, 52, 26, 13, 42, 51, 22, 30
OFFSET
1,2
LINKS
FORMULA
a(n) = Sum_{d|n} A349137(d).
PROG
(PARI)
A349137(n) = eulerphi((1+(n>>valuation(n, 2)))/2);
A349138(n) = sumdiv(n, d, A349137(d));
CROSSREFS
Cf. also A349122.
Sequence in context: A353936 A110266 A377107 * A309067 A205561 A323636
KEYWORD
nonn,look
AUTHOR
Antti Karttunen, Nov 13 2021
STATUS
approved