A353674 - OEIS

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A353674

a(n) = 1 if n is an even number with an odd number of distinct prime factors, otherwise 0.

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

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OFFSET

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..65537

Index entries for characteristic functions

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