login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A064015 Numbers n such that sopf(n)*nud(n)==pi(n), where sopf(n)=A008472, nud(n)=A034444 and pi(n)=A000720. 0
1, 8, 72, 135, 504, 726, 3431, 5313, 8614, 10249 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..10.

PROG

(PARI) nud(n) = 2^omega(n); pi(n) = s=0; for(x=1, n, if(isprime(x), s++)); s; sopf(n, s, fac, i)=fac=factor(n); for(i=1, matsize(fac)[1], s=s+fac[i, 1]); return(s); for(n=1, 10^6, if(sopf(n)*nud(n)==pi(n), print(n)))

CROSSREFS

Cf. A008472, A034444, A000720.

Sequence in context: A115693 A112403 A043932 * A044576 A104453 A254371

Adjacent sequences:  A064012 A064013 A064014 * A064016 A064017 A064018

KEYWORD

more,nonn

AUTHOR

Jason Earls, Sep 06 2001

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified September 21 22:00 EDT 2019. Contains 327283 sequences. (Running on oeis4.)