The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons 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 56th year, we are closing in on 350,000 sequences, and we’ve crossed 9,700 citations (which often say “discovered thanks to the OEIS”).

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A302088 Numbers k such that 5*k^k + 4 is prime. 2
 3, 5, 9, 183, 561 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Next term, if it exists, is greater than 5000. LINKS MATHEMATICA Select[Range[1, 1000], PrimeQ[5*#^# + 4] &] (* Vaclav Kotesovec, Apr 01 2018 *) PROG (PARI) for(n=0, 500, if(isprime(5*n^n+4), print1(n", "))) (PARI) lista(nn) = forstep(n=1, nn, 2, if(ispseudoprime(5*n^n+4), print1(n, ", "))); \\ Altug Alkan, Apr 01 2018 CROSSREFS Numbers k such that b*k^k + b - 1 is prime: A110932 (b=2), A160360 (b=3), A301520 (b=4), this sequence (b=5), A302090 (b=6). Cf. A302089. Sequence in context: A121622 A188983 A083519 * A211414 A173706 A332359 Adjacent sequences:  A302085 A302086 A302087 * A302089 A302090 A302091 KEYWORD nonn,more,hard AUTHOR Seiichi Manyama, Apr 01 2018 EXTENSIONS a(5) from Vaclav Kotesovec, Apr 01 2018 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.

Last modified December 2 20:25 EST 2021. Contains 349445 sequences. (Running on oeis4.)