A384812 If n = Product prime(i)^e(i) then a(n) = Sum prime(e(i)).

0, 2, 2, 3, 2, 4, 2, 5, 3, 4, 2, 5, 2, 4, 4, 7, 2, 5, 2, 5, 4, 4, 2, 7, 3, 4, 5, 5, 2, 6, 2, 11, 4, 4, 4, 6, 2, 4, 4, 7, 2, 6, 2, 5, 5, 4, 2, 9, 3, 5, 4, 5, 2, 7, 4, 7, 4, 4, 2, 7, 2, 4, 5, 13, 4, 6, 2, 5, 4, 6, 2, 8, 2, 4, 5, 5, 4, 6, 2, 9, 7, 4, 2, 7, 4, 4, 4, 7, 2, 7

Offset

1,2

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Index entries for sequences computed from exponents in factorization of n.

Index entries for sequences computed from indices in prime factorization.

Maple

f:= proc(n) local t;
  add(ithprime(t[2]), t=ifactors(n)[2])
end proc:
map(f, [$1..100]); # Robert Israel, Jul 25 2025

Mathematica

Table[Plus @@ (Prime[#[[2]]] & /@ FactorInteger[n]), {n, 1, 90}]

Prog

(PARI) a(n) = my(f=factor(n)); sum(k=1, #f~, prime(f[k, 2])); \\ Michel Marcus, Jun 10 2025

Crossrefs

Cf. A001222, A001414, A008472, A066328, A181819, A366988.

Sequence in context: A348554 A333970 A338138 * A369760 A305899 A101296

Adjacent sequences: A384809 A384810 A384811 * A384813 A384814 A384815

Keyword

nonn

Author

Ilya Gutkovskiy, Jun 10 2025

Status

approved