

A344875


Multiplicative with a(2^e) = 2^(1+e)  1, and a(p^e) = p^e  1 for odd primes p.


19



1, 3, 2, 7, 4, 6, 6, 15, 8, 12, 10, 14, 12, 18, 8, 31, 16, 24, 18, 28, 12, 30, 22, 30, 24, 36, 26, 42, 28, 24, 30, 63, 20, 48, 24, 56, 36, 54, 24, 60, 40, 36, 42, 70, 32, 66, 46, 62, 48, 72, 32, 84, 52, 78, 40, 90, 36, 84, 58, 56, 60, 90, 48, 127, 48, 60, 66, 112, 44, 72, 70, 120, 72, 108, 48, 126, 60, 72, 78, 124, 80, 120
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,2


LINKS

Antti Karttunen, Table of n, a(n) for n = 1..10000


FORMULA

a(n) = A344878(n) * A344879(n).
Multiplicative with a(p^e) = A153151(p^e).  Antti Karttunen, Jul 01 2021


MATHEMATICA

f[2, e_] := 2^(e + 1)  1; f[p_, e_] := p^e  1; a[1] = 1; a[n_] := Times @@ f @@@ FactorInteger[n]; Array[a, 100] (* Amiram Eldar, Jun 03 2021 *)


PROG

(PARI) A344875(n) = { my(f=factor(n)~); prod(i=1, #f, (f[1, i]^(f[2, i]+(2==f[1, i]))1)); };


CROSSREFS

Cf. A047994, A153151, A344876, A344877, A344878, A344879, A344969, A345947.
Sequence in context: A341911 A341916 A344878 * A178910 A182651 A175055
Adjacent sequences: A344872 A344873 A344874 * A344876 A344877 A344878


KEYWORD

nonn,mult


AUTHOR

Antti Karttunen, Jun 03 2021


STATUS

approved



