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A373156
a(n) = 1 if the 2-adic and the 3-adic valuations of n are equal, otherwise 0.
2
1, 0, 0, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0, 0, 0, 1, 1, 1, 0, 0, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1
OFFSET
1
FORMULA
a(n) = [A007814(n) == A007949(n)], where [ ] is the Iverson bracket.
Sum_{k=1..n} a(k) ~ (2/5) * n. - Amiram Eldar, May 31 2024
MATHEMATICA
a[n_] := Boole[IntegerExponent[n, 2] == IntegerExponent[n, 3]];
Table[a[n], {n, 1, 121}] (* Robert P. P. McKone, May 28 2024 *)
PROG
(PARI) A373156(n) = (valuation(n, 2)==valuation(n, 3));
CROSSREFS
Characteristic function of A064615.
Sequence in context: A071906 A104107 A120532 * A320106 A303561 A284680
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 28 2024
STATUS
approved