

A121617


Numbers n such that A022521(n1) = n^5  (n1)^5 is prime.


7



2, 3, 6, 11, 17, 20, 25, 28, 31, 32, 35, 36, 42, 45, 47, 55, 58, 65, 67, 76, 79, 86, 88, 89, 100, 102, 105, 110, 111, 113, 121, 122, 145, 149, 166, 175, 179, 193, 198, 211, 218, 223, 226, 230, 240, 244, 245, 256, 262, 287, 292, 295, 297, 298, 300
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OFFSET

1,1


COMMENTS

The elements of A022521 are sometimes called Nexus number of order 5, see there.
The terms should have 1 subtracted, since indices of primes in A022521 are 1, 2, 5, 10, 16, 19, 24, 27, 30, 31, 34, 35, 41, 44, 46, ....  M. F. Hasler, Jan 27 2013
Corresponding Nexus Primes of order 5 (or primes of form (n+1)^5  n^5 = A022521(n)) are listed in A121616 = {31, 211, 4651, 61051, 371281, 723901, 1803001, 2861461, ...}.


LINKS



MAPLE

select(t > isprime(t^5(t1)^5), [$1..1000]); # Robert Israel, Jul 10 2018


MATHEMATICA

Do[np5=n^5  (n1)^5; If[PrimeQ[np5], Print[n]], {n, 1, 100}]
Flatten[Position[Partition[Range[300]^5, 2, 1], _?(PrimeQ[#[[2]]#[[1]]]&), 1, Heads> False]]+1 (* Harvey P. Dale, May 30 2021 *)


PROG

(PARI) A121617(n, print_all=0)={for(k=2, 9e9, ispseudoprime(k^5(k1)^5) & !(print_all & print1(k", ")) & !n & return(k))} \\ M. F. Hasler, Feb 03 2013


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



