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A327938
Multiplicative with a(p^e) = p^(e mod p).
16
1, 2, 3, 1, 5, 6, 7, 2, 9, 10, 11, 3, 13, 14, 15, 1, 17, 18, 19, 5, 21, 22, 23, 6, 25, 26, 1, 7, 29, 30, 31, 2, 33, 34, 35, 9, 37, 38, 39, 10, 41, 42, 43, 11, 45, 46, 47, 3, 49, 50, 51, 13, 53, 2, 55, 14, 57, 58, 59, 15, 61, 62, 63, 1, 65, 66, 67, 17, 69, 70, 71, 18, 73, 74, 75, 19, 77, 78, 79, 5, 3, 82, 83, 21, 85, 86, 87, 22
OFFSET
1,2
COMMENTS
All terms are in A048103.
LINKS
FORMULA
Multiplicative with a(p^e) = p^(e mod p).
a(n) = n / A327939(n).
For all n, A129251(a(n)) = 0, A327936(a(n)) = 1.
Sum_{k=1..n} a(k) ~ c * n^2, where c = (1/2) * Product_{p prime} (1/(1+1/p^p)) = 0.38559042841678887219... . - Amiram Eldar, Nov 07 2022
MATHEMATICA
f[p_, e_] := p^Mod[e, p]; a[n_] := Times @@ f @@@ FactorInteger[n]; Array[a, 100] (* Amiram Eldar, Nov 07 2022 *)
PROG
(PARI) A327938(n) = { my(f = factor(n)); for(k=1, #f~, f[k, 2] = (f[k, 2]%f[k, 1])); factorback(f); };
CROSSREFS
Differs from A065883 for the first time at n=27.
Sequence in context: A366244 A083346 A319652 * A065883 A214392 A071975
KEYWORD
nonn,mult
AUTHOR
Antti Karttunen, Oct 01 2019
STATUS
approved