The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
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!)
A058911 Numbers k such that k^k + k + 1 is prime. 3
0, 1, 2, 3, 6, 9, 462 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
COMMENTS
There is no further term up to 10000. - Farideh Firoozbakht, Nov 11 2006
If it exists, a(8) > 32100. - Dmitry Petukhov, Sep 14 2021
LINKS
EXAMPLE
a(2) = 2 because 2^2 + 2 + 1 = 7.
MATHEMATICA
Do[ If[ PrimeQ[ n^n + n + 1], Print[n]], {n, 1, 700} ]
Join[{0}, Select[Range[470], PrimeQ[#^#+#+1]&]] (* Harvey P. Dale, Dec 11 2022 *)
PROG
(PARI) f2(n, k) = for(x=1, n, y=x^x+x+k; if(ispseudoprime(y), print1(x", "))) \\ Cino Hilliard, Jan 07 2005
(PFGW) ABC2 $a^$a + $a + 1
a: from 0 to 1000 // Jinyuan Wang, Mar 01 2020
CROSSREFS
Cf. A058912 (k^k + k - 1 is prime), A161471 (corresponding primes).
Sequence in context: A071714 A077753 A353122 * A249247 A276956 A276946
KEYWORD
nonn,hard,more
AUTHOR
Felice Russo, Jan 10 2001
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 June 17 18:36 EDT 2024. Contains 373463 sequences. (Running on oeis4.)