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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A090186 a(n) is the least prime of the form prime(n)# * k + prime(n+1). 1
5, 11, 37, 431, 13873, 30047, 510529, 9699713, 446185769, 51757545871, 601681470427, 22262214404471, 2434002108217723, 13082761331670077, 1229779565176982873, 32589158477190044789, 1922760350154212639131 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

# denotes primorial; k >= 1.

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..300

EXAMPLE

a(4)=431 because prime(4)#*2+prime(5) = 431 is prime.

MATHEMATICA

lp[{a_, b_}]:=Module[{k=1}, While[!PrimeQ[k*a+b], k++]; k*a+b]; With[{nn=20}, lp/@Thread[ {FoldList[Times, Prime[Range[nn]]], Prime[Range[2, nn+1]]}]] (* Harvey P. Dale, Dec 25 2018 *)

CROSSREFS

Sequence in context: A152563 A077466 A074626 * A205719 A139515 A038708

Adjacent sequences:  A090183 A090184 A090185 * A090187 A090188 A090189

KEYWORD

nonn

AUTHOR

Pierre CAMI, Jan 21 2004

EXTENSIONS

Edited by Don Reble, May 07 2006

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 June 19 23:01 EDT 2019. Contains 324222 sequences. (Running on oeis4.)