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!)
A242178 Numbers k such that k*8^k + 1 is prime. 3
5, 17, 23, 1911, 20855, 35945, 42816 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

G. Loeh, Generalized Cullen primes

MATHEMATICA

Select[Range[2000], PrimeQ[# 8^# + 1] &]

PROG

(MAGMA) [n: n in [0..2000] | IsPrime(n*8^n+1)];

(PARI) is(n)=ispseudoprime(n*8^n+1) \\ Charles R Greathouse IV, May 22 2017

CROSSREFS

Cf. similar sequences listed in A242176.

Sequence in context: A097434 A106012 A230527 * A063588 A307286 A117635

Adjacent sequences:  A242175 A242176 A242177 * A242179 A242180 A242181

KEYWORD

nonn,more

AUTHOR

Vincenzo Librandi, May 08 2014

EXTENSIONS

a(5)-a(7) from Loeh's list (see Links) - Bruno Berselli, May 08 2014

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 April 10 02:20 EDT 2020. Contains 333392 sequences. (Running on oeis4.)