A063795 Numbers k such that usigma(k) = phi(k)*omega(k), where omega(k) is the number of distinct prime divisors of k.

35, 99, 357, 495, 1672, 2108, 3135, 3465, 3692, 5152, 11704, 14756, 15800, 18375, 20026, 23374, 23560, 25714, 25844, 33915, 35074, 39585, 49196, 55154, 56134, 66040, 86900, 99484, 104140, 105105, 110600, 116116, 124558, 141340, 157586

Offset

1,1

Links

Harry J. Smith, Table of n, a(n) for n = 1..200

Prog

(PARI) us(n) = sumdiv(n, d, if(gcd(d, n/d)==1, d));
for(n=1, 10^7, if(us(n)==eulerphi(n)*omega(n), print(n)))
(PARI) us(n) = sumdiv(n, d, if(gcd(d, n/d)==1, d))
{ n=0; for (m=1, 10^9, if(us(m)==eulerphi(m)*omega(m), write("b063795.txt", n++, " ", m); if (n==200, break)) ) } \\ Harry J. Smith, Aug 31 2009

Crossrefs

Cf. A034448.

Sequence in context: A259978 A044222 A044603 * A282851 A015882 A347384

Adjacent sequences: A063792 A063793 A063794 * A063796 A063797 A063798

Keyword

nonn

Author

Jason Earls, Aug 18 2001

Status

approved