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A295660
Binary weight of Euler phi: a(n) = A000120(A000010(n)).
6
1, 1, 1, 1, 1, 1, 2, 1, 2, 1, 2, 1, 2, 2, 1, 1, 1, 2, 2, 1, 2, 2, 3, 1, 2, 2, 2, 2, 3, 1, 4, 1, 2, 1, 2, 2, 2, 2, 2, 1, 2, 2, 3, 2, 2, 3, 4, 1, 3, 2, 1, 2, 3, 2, 2, 2, 2, 3, 4, 1, 4, 4, 2, 1, 2, 2, 2, 1, 3, 2, 3, 2, 2, 2, 2, 2, 4, 2, 4, 1, 4, 2, 3, 2, 1, 3, 3, 2, 3, 2, 2, 3, 4, 4, 2, 1, 2, 3, 4, 2, 3, 1, 4, 2, 2
OFFSET
1,7
FORMULA
a(n) = A000120(A000010(n)).
MATHEMATICA
Array[DigitCount[EulerPhi@ #, 2, 1] &, 105] (* Michael De Vlieger, Nov 27 2017 *)
PROG
(PARI) A295660(n) = hammingweight(eulerphi(n));
(Scheme) (define (A295660 n) (A000120 (A000010 n)))
CROSSREFS
Cf. A003401 (gives the positions of ones).
Sequence in context: A160978 A231776 A055734 * A193169 A193453 A227944
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 27 2017
STATUS
approved