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A359594
Multiplicative with a(p^e) = p^e if p divides e, 1 otherwise.
2
1, 1, 1, 4, 1, 1, 1, 1, 1, 1, 1, 4, 1, 1, 1, 16, 1, 1, 1, 4, 1, 1, 1, 1, 1, 1, 27, 4, 1, 1, 1, 1, 1, 1, 1, 4, 1, 1, 1, 1, 1, 1, 1, 4, 1, 1, 1, 16, 1, 1, 1, 4, 1, 27, 1, 1, 1, 1, 1, 4, 1, 1, 1, 64, 1, 1, 1, 4, 1, 1, 1, 1, 1, 1, 1, 4, 1, 1, 1, 16, 1, 1, 1, 4, 1, 1, 1, 1, 1, 1, 1, 4, 1, 1, 1, 1, 1, 1, 1, 4, 1, 1, 1, 1, 1, 1, 1, 108
OFFSET
1,4
COMMENTS
Each term a(n) divides both A085731(n) and A327939(n).
LINKS
FORMULA
a(n) = n / A359593(n).
MATHEMATICA
f[p_, e_] := If[Divisible[e, p], p^e, 1]; a[1] = 1; a[n_] := Times @@ f @@@ FactorInteger[n]; Array[a, 100] (* Amiram Eldar, Jan 09 2023 *)
PROG
(PARI) A359594(n) = { my(f = factor(n)); prod(k=1, #f~, f[k, 1]^(f[k, 2]*!(f[k, 2]%f[k, 1]))); };
(Python)
from math import prod
from sympy import factorint
def A359594(n): return prod(p**e for p, e in factorint(n).items() if not e%p) # Chai Wah Wu, Jan 10 2023
CROSSREFS
Cf. A359593.
Cf. also A085731, A327939.
Sequence in context: A370703 A365487 A368172 * A368331 A366145 A204160
KEYWORD
nonn,mult
AUTHOR
Antti Karttunen, Jan 09 2023
STATUS
approved