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A353674
a(n) = 1 if n is an even number with an odd number of distinct prime factors, otherwise 0.
4
0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0
OFFSET
1
FORMULA
a(n) = A059841(n) * A092248(n).
a(n) = A059841(n) - A353674(n).
a(n) = A092248(n) - A353673(n).
MATHEMATICA
Table[If[EvenQ[n]&&OddQ[PrimeNu[n]], 1, 0], {n, 140}] (* Harvey P. Dale, Jul 16 2023 *)
PROG
(PARI) A353674(n) = (!(n%2) && (omega(n)%2));
CROSSREFS
Characteristic function of A098904.
Cf. also A353556.
Sequence in context: A288223 A353811 A116865 * A288512 A157687 A189668
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 03 2022
STATUS
approved