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A063795 Numbers k such that usigma(k) = phi(k)*omega(k), where omega(k) is the number of distinct prime divisors of k. 1
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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified September 22 22:13 EDT 2021. Contains 347608 sequences. (Running on oeis4.)