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A353556
a(n) = 1 if n is an even number with an odd number of prime factors (counted with multiplicity), otherwise 0.
11
0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1
OFFSET
1
FORMULA
a(n) = A059841(n) * A066829(n).
a(n) = A059841(n) - A353555(n).
a(n) = A066829(n) - A353558(n).
MATHEMATICA
Table[If[EvenQ[n]&&OddQ[PrimeOmega[n]], 1, 0], {n, 150}] (* Harvey P. Dale, Jan 12 2024 *)
PROG
(PARI) A353556(n) = ((!(n%2))&&(bigomega(n)%2));
CROSSREFS
Characteristic function of A046470.
Sequence in context: A330306 A300477 A355202 * A228495 A356982 A284683
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 01 2022
STATUS
approved