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

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A153355 Numbers k such that 5k-1 is a prime. 3
4, 6, 12, 16, 18, 22, 28, 30, 36, 40, 46, 48, 54, 70, 72, 76, 78, 82, 84, 88, 90, 96, 100, 102, 114, 120, 124, 132, 142, 144, 148, 154, 162, 166, 168, 172, 184, 186, 202, 204, 208, 210, 214, 222, 226, 246, 250, 252, 256, 258, 264, 280, 282, 286, 288, 292, 298 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

One more than the value of A024897 at the same index. - R. J. Mathar, Jan 05 2009

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

FORMULA

The set of numbers (1+A030433(k))/5, k=1,2,3,4,.... - R. J. Mathar, Jan 03 2009

EXAMPLE

5*4 - 1 = 19 is a prime, so 4 is a term;

5*30 - 1 = 149 is a prime, so 30 is a term.

MATHEMATICA

Select[Range[400], PrimeQ[5#-1]&] (* Vladimir Joseph Stephan Orlovsky, Feb 25 2011*)

PROG

(Magma) [n: n in [0..300] | IsPrime(5*n - 1)]; // Vincenzo Librandi, Sep 24 2012

CROSSREFS

Sequence in context: A104236 A265225 A122781 * A341274 A310597 A310598

Adjacent sequences:  A153352 A153353 A153354 * A153356 A153357 A153358

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, Dec 24 2008

EXTENSIONS

Extended by R. J. Mathar, Jan 05 2009

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.

License Agreements, Terms of Use, Privacy Policy. .

Last modified September 30 22:28 EDT 2022. Contains 357107 sequences. (Running on oeis4.)