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

 Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 59th year, we have over 358,000 sequences, and we’ve crossed 10,300 citations (which often say “discovered thanks to the OEIS”). Other ways to Give
 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A075548 Perfect powers n such that (n-17)/2 is prime. 1
 27, 243, 343, 19683, 29791, 300763, 421875, 493039, 658503, 759375, 1367631, 2048383, 2685619, 3176523, 4019679, 5000211, 8869743, 9393931, 15069223, 17373979, 19034163, 25672375, 32461759, 43243551, 52734375, 54439939, 63521199, 82312875, 84604519 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Charlie Neder, Table of n, a(n) for n = 1..865 EXAMPLE a(1)=3^3, a(2)=3^5, a(3)=7^3, a(4)=3^9, a(5)=31^3, a(6)=67^3, a(7)=75^3, a(8)=79^3, a(9)=87^3, a(10)=15^5, a(11)=111^3, a(12)=127^3, a(13)=139^3, a(14)=147^3, a(15)=159^3, a(16)=171^3, a(17)=207^3 and a(18)=211^3. MATHEMATICA pp = Join[{1}, Select[ Range[10^7], Apply[GCD, Last[ Transpose[ FactorInteger[ # ]]]] > 1 & ]]; Select[pp, PrimeQ[(# - 17)/2] & ] Select[Flatten[Table[n^Range[2, 10], {n, 250}]], PrimeQ[(#-17)/2]&]//Union (* Harvey P. Dale, Dec 08 2018 *) CROSSREFS Sequence in context: A069979 A183806 A207104 * A345054 A074117 A030509 Adjacent sequences: A075545 A075546 A075547 * A075549 A075550 A075551 KEYWORD easy,nonn AUTHOR Zak Seidov, Oct 11 2002 EXTENSIONS Extended by Robert G. Wilson v, Oct 14 2002 a(19)-a(29) from Charlie Neder, Feb 11 2019 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 December 1 01:13 EST 2022. Contains 358453 sequences. (Running on oeis4.)