A178652 Primes of the form 4^k + 13^2.

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.

Links

Table of n, a(n) for n=1..11.

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

Cf. A176969, A176978, A177833.

Sequence in context: A261530 A246135 A140002 * A119567 A142436 A322842

Adjacent sequences: A178649 A178650 A178651 * A178653 A178654 A178655

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