OFFSET
1,1
LINKS
T. D. Noe, Table of n, a(n) for n = 1..1000
Will Nicholes, Prime Signatures
FORMULA
Sum_{n>=1} 1/a(n) = (P(5)^2 - P(10))/2 = (A085965^2 - P(10))/2 = 0.000142..., where P is the prime zeta function. - Amiram Eldar, Jul 06 2020
MATHEMATICA
f[n_]:=Sort[Last/@FactorInteger[n]]=={1, 1}; Select[Range[10000], f]^5
PROG
(PARI) list(lim)=my(v=List(), t); forprime(p=2, lim^(1/10), t=p^5; forprime(q=p+1, (lim\t)^(1/5), listput(v, t*q^5))); vecsort(Vec(v)) \\ Charles R Greathouse IV, Jul 20 2011
CROSSREFS
KEYWORD
nonn
AUTHOR
Vladimir Joseph Stephan Orlovsky, May 10 2011
STATUS
approved