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A293439 Number of odious exponents in the prime factorization of n. 4
0, 1, 1, 1, 1, 2, 1, 0, 1, 2, 1, 2, 1, 2, 2, 1, 1, 2, 1, 2, 2, 2, 1, 1, 1, 2, 0, 2, 1, 3, 1, 0, 2, 2, 2, 2, 1, 2, 2, 1, 1, 3, 1, 2, 2, 2, 1, 2, 1, 2, 2, 2, 1, 1, 2, 1, 2, 2, 1, 3, 1, 2, 2, 0, 2, 3, 1, 2, 2, 3, 1, 1, 1, 2, 2, 2, 2, 3, 1, 2, 1, 2, 1, 3, 2, 2, 2, 1, 1, 3, 2, 2, 2, 2, 2, 1, 1, 2, 2, 2, 1, 3, 1, 1, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,6

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..16384

Index entries for sequences computed from exponents in factorization of n

FORMULA

Additive with a(p^e) = A010060(e).

a(n) = A007814(A293443(n)).

EXAMPLE

For n = 2 = 2^1, the only exponent 1 is odious (that is, has an odd Hamming weight and thus is included in A000069), so a(2) = 1.

For n = 24 = 2^3 * 3^1, the exponent 3 (with binary representation "11") is evil (has an even Hamming weight and thus is included in A001969), while the other exponent 1 is odious, so a(24) = 1.

PROG

(PARI) A293439(n) = vecsum(apply(e -> (hammingweight(e)%2), factorint(n)[, 2]));

CROSSREFS

Cf. A000069, A010060, A293443.

Cf. A270428 (numbers such that a(n) = A001221(n)).

Differs from A144095 for the first time at n=24.

Sequence in context: A038698 A263233 A087991 * A144095 A076092 A080468

Adjacent sequences:  A293436 A293437 A293438 * A293440 A293441 A293442

KEYWORD

nonn

AUTHOR

Antti Karttunen, Nov 01 2017

STATUS

approved

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Last modified May 26 21:38 EDT 2018. Contains 304645 sequences. (Running on oeis4.)