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A216423
Numbers k such that 4^k + k^4 + 1 is prime.
3
0, 6, 12, 3804, 8346, 15528, 147036
OFFSET
1,2
COMMENTS
a(8) > 2*10^5. - Robert Price, Apr 29 2014
a(1)-a(3) are trivially prime. a(4)-a(7) are probable primes. - Robert Price, May 07 2014
MATHEMATICA
Select[Range[0, 5000], PrimeQ[4^# + #^4 + 1] &]
PROG
(PARI) is(n)=ispseudoprime(4^n+n^4+1) \\ Charles R Greathouse IV, Jun 06 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
Vincenzo Librandi, Sep 07 2012
EXTENSIONS
a(5)-a(7) from Robert Price, Apr 29 2014
STATUS
approved