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A220701
Numbers k such that k^3 + 3*k + 3^k is prime.
1
1, 2, 4, 5, 7, 17, 22, 47, 155, 167, 203, 277, 469, 629, 890, 1427, 4507, 5705, 6095, 9808, 10108, 12797, 16184, 31535, 33575
OFFSET
1,2
COMMENTS
a(26) > 10^5. - Michael S. Branicky, Oct 25 2024
MATHEMATICA
Select[Range[10000], PrimeQ[#^3 + 3*# + 3^#]&]
PROG
(PARI) is(n)=ispseudoprime(n^3+3*n+3^n) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Cf. A220509.
Sequence in context: A019277 A127791 A290431 * A005620 A049915 A244332
KEYWORD
nonn,more,changed
AUTHOR
Vincenzo Librandi, Jan 07 2013
EXTENSIONS
a(21)-a(25) from Michael S. Branicky, Jul 13 2023
STATUS
approved