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A353673
a(n) = 1 if n is an odd number with an odd number of distinct prime factors, otherwise 0.
4
0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1
OFFSET
1
FORMULA
a(n) = A000035(n) * A092248(n).
a(n) = A000035(n) - A353675(n).
a(n) = A092248(n) - A353674(n).
EXAMPLE
n = 9 = 3^2 is an odd number with an odd number of distinct prime factors, therefore a(9) = 1.
n = 105 = 3*5*7 is an odd number with an odd number of distinct prime factors, therefore a(105) = 1.
PROG
(PARI) A353673(n) = ((n%2) && (omega(n)%2));
CROSSREFS
Characteristic function of A098903.
Differs from A174275 for the first time at n=105, where a(105) = 1, while A174275(105) = 0.
Cf. also A353558.
Sequence in context: A327253 A051840 A174275 * A144599 A144608 A327208
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 03 2022
STATUS
approved