The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A060848 Difference between a nontrivial prime power (A025475) and the next prime. 1
 1, 3, 2, 1, 4, 2, 5, 4, 3, 2, 6, 2, 3, 4, 8, 1, 4, 4, 6, 9, 12, 6, 4, 12, 6, 7, 30, 4, 12, 12, 5, 16, 6, 4, 10, 10, 12, 10, 6, 3, 4, 6, 10, 4, 6, 2, 4, 10, 6, 17, 4, 10, 4, 18, 6, 30, 12, 12, 4, 10, 27, 4, 6, 4, 12, 4, 28, 6, 2, 10, 4, 4, 10, 12, 18, 10, 10, 3, 12, 4, 12, 6, 10, 10, 18, 10, 12 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(n)=1 only for some powers of 2 corresponding to Fermat primes > 3. - Edited by Robert Israel, Jun 03 2021 LINKS Robert Israel, Table of n, a(n) for n = 1..10000 FORMULA a(n) = nextprime(A025475(n)) - A025475(n) = A013632(A025475(n)). EXAMPLE 78125=5^7 is followed by 78137, the difference is 12. MAPLE N:= 10^5: # for prime powers <= N S:= {}: p:= 1: do p:= nextprime(p); if p^2 > N then break fi; S:= S union {seq(p^i, i=2..floor(log[p](N)))} od: map(t -> nextprime(t)-t, sort(convert(S, list))); # Robert Israel, Jun 03 2021 MATHEMATICA NextPrime[#]-#&/@Select[Range[100000], PrimePowerQ[#]&&!PrimeQ[#]&] (* Harvey P. Dale, Oct 19 2022 *) CROSSREFS Cf. A025475, A007918, A013632. Sequence in context: A264597 A112603 A097294 * A265271 A350499 A006020 Adjacent sequences: A060845 A060846 A060847 * A060849 A060850 A060851 KEYWORD nonn AUTHOR Labos Elemer, May 03 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 | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified May 18 14:55 EDT 2024. Contains 372640 sequences. (Running on oeis4.)