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A178652
Primes of the form 4^k + 13^2.
1
173, 233, 1193, 16553, 262313, 67109033, 1073741993, 4611686018427388073, 73786976294838206633, 19807040628566084398385987753, 1361129467683753853853498429727072845993
OFFSET
1,1
COMMENTS
Necessarily k is odd, 4^2 + 13^2 a multiple of 5.
EXAMPLE
a(1) = 4^1 + 13^2 = 173.
a(2) = 4^3 + 13^2 = 233.
a(11) = 4^65 + 13^2 = 1361129467683753853853498429727072845993.
a(12) = 4^99 + 13^2 = 401734511064747568885490523085290650630550748445698208825513.
MATHEMATICA
Select[4^Range[0, 70]+13^2, PrimeQ] (* Harvey P. Dale, Mar 05 2015 *)
PROG
(PARI) forstep(n=1, 999, 2, if(ispseudoprime(t=4^n+169), print1(t", "))) \\ Charles R Greathouse IV, Aug 27 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Eva-Maria Zschorn (e-m.zschorn(AT)zaschendorf.km3.de), Jun 01 2010
EXTENSIONS
New name from Charles R Greathouse IV, Aug 27 2013
STATUS
approved