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A331738
Multiplicative with a(p^e) = p^(e-A000265(e)), where A000265(x) gives the odd part of x.
3
1, 1, 1, 2, 1, 1, 1, 1, 3, 1, 1, 2, 1, 1, 1, 8, 1, 3, 1, 2, 1, 1, 1, 1, 5, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 6, 1, 1, 1, 1, 1, 1, 1, 2, 3, 1, 1, 8, 7, 5, 1, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 3, 8, 1, 1, 1, 2, 1, 1, 1, 3, 1, 1, 5, 2, 1, 1, 1, 8, 27, 1, 1, 2, 1, 1, 1, 1, 1, 3, 1, 2, 1, 1, 1, 1, 1, 7, 3, 10, 1, 1, 1, 1, 1
OFFSET
1,4
FORMULA
Multiplicative with a(p^e) = p^A331739(e).
a(n) = n / A331737(n).
MATHEMATICA
f[p_, e_] := p^(e - e/2^IntegerExponent[e, 2]); a[1] = 1; a[n_] := Times @@ f @@@ FactorInteger[n]; Array[a, 100] (* Amiram Eldar, Nov 24 2022 *)
PROG
(PARI)
A000265(n) = (n>>valuation(n, 2));
A331738(n) = { my(f = factor(n)); prod(k=1, #f~, f[k, 1]^(f[k, 2]-A000265(f[k, 2]))); };
CROSSREFS
KEYWORD
nonn,mult
AUTHOR
Antti Karttunen, Feb 02 2020
STATUS
approved