The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A078752 Least m>n such that phi(m) >= 2*phi(n), where phi is Euler's totient function (A000010). 1
 3, 3, 5, 5, 11, 7, 13, 11, 13, 11, 23, 13, 29, 17, 17, 17, 37, 19, 37, 23, 29, 23, 47, 25, 41, 29, 37, 29, 59, 31, 61, 37, 41, 37, 53, 37, 73, 41, 53, 41, 83, 43, 89, 47, 53, 47, 97, 49, 89, 53, 67, 53, 107, 55, 83, 59, 73, 59, 127, 61, 127, 67, 73, 67, 97, 67, 137, 71, 89, 71 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS For odd primes p: a(p-1) = p; the converse is not true, as e.g. a(25-1)=25. LINKS Harvey P. Dale, Table of n, a(n) for n = 1..1000 MATHEMATICA epm[n_]:=Module[{m=n+1, epn2=2EulerPhi[n]}, While[EulerPhi[m]

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

Last modified September 8 21:25 EDT 2024. Contains 375759 sequences. (Running on oeis4.)