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A356170
a(n) = 1 if A001222(n) == 2*A007814(n), and otherwise 0, where A001222 is bigomega (number of prime factors with multiplicity) and A007814 is the 2-adic valuation of n.
2
1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 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, 0, 0, 1, 0, 1, 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, 1
OFFSET
1
MATHEMATICA
Array[Boole[PrimeOmega[#] == 2 IntegerExponent[#, 2]] &, 122] (* Michael De Vlieger, Nov 02 2022 *)
PROG
(PARI) A356170(n) = (bigomega(n) == 2*valuation(n, 2));
CROSSREFS
Characteristic function of A072978.
Sequence in context: A014184 A014359 A079998 * A353629 A339661 A374471
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 02 2022
STATUS
approved