login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A229902 a(n) is the smallest m such that 19*m^k+1 is prime for k=1, 2,...,n. 1
10, 10, 10, 2080, 178030, 41697270, 4355942080 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

10 divides all terms.

LINKS

Table of n, a(n) for n=1..7.

MATHEMATICA

a[1]=10; a[n_]:=a[n]=(For[m=a[n-1]/10, Union[Table[PrimeQ[19(10m)^k+1], {k, n}]]=={True}, m++]; 10m) (* Farideh Firoozbakht Oct 05 2013 *)

CROSSREFS

Cf. A106759, A166459, A229906, A229626.

Sequence in context: A178166 A003855 A245431 * A004209 A162720 A112867

Adjacent sequences:  A229899 A229900 A229901 * A229903 A229904 A229905

KEYWORD

nonn,more

AUTHOR

Jahangeer Kholdi, Oct 04 2013

EXTENSIONS

a(7) from Farideh Firoozbakht Oct 05 2013

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 September 24 04:04 EDT 2020. Contains 337316 sequences. (Running on oeis4.)