OFFSET
1,1
COMMENTS
Smallest k such that sopf(k) = n * m^q where m, q >= 2.
a(n) = A213386(n) except for n = 20, 32, 48, ...
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
EXAMPLE
a(20) = 471 = 3*157, since the sum of the distinct prime divisors is 160 = 20*2^3.
MAPLE
with (numtheory):
sopf:= proc(n) option remember;
add(i, i=factorset(n))
end:
a:= proc(n) local k, q;
for k while irem(sopf(k), n, 'q')>0 or
igcd (map(i->i[2], ifactors(q)[2])[])<2 do od; k
end:
seq (a(n), n=1..100);
CROSSREFS
KEYWORD
nonn
AUTHOR
Michel Lagneau, Jun 27 2012
STATUS
approved