

A025584


Primes p such that p2 is not a prime.


19



2, 3, 11, 17, 23, 29, 37, 41, 47, 53, 59, 67, 71, 79, 83, 89, 97, 101, 107, 113, 127, 131, 137, 149, 157, 163, 167, 173, 179, 191, 197, 211, 223, 227, 233, 239, 251, 257, 263, 269, 277, 281, 293, 307, 311, 317, 331, 337, 347, 353, 359, 367, 373, 379, 383, 389, 397, 401
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OFFSET

1,1


COMMENTS

Primes p (for p>=11) such that sigma(p2) > p.  Benoit Cloitre, Feb 08 2002
Prime numbers that are not the sum of two smaller prime numbers.  Tomas Xordan, May 10 2007


LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..10000


FORMULA

a(n) ~ n log n.  Charles R Greathouse IV, Jan 10 2013


MATHEMATICA

Select[ Prime /@ Range[100], ! PrimeQ[#  2] &] (* JeanFrançois Alcover, Apr 19 2013 *)


PROG

(MAGMA) [p: p in PrimesUpTo(420)  not IsPrime(p2)]; // Vincenzo Librandi, Jul 26 2013
(PARI) lista(nn) = forprime(p=2, nn, if (!isprime(p2), print1(p, ", ")); ); \\ Michel Marcus, Dec 05 2015


CROSSREFS

Complement of A006512 in A000040.
Cf. A014092.
Sequence in context: A100962 A045337 A098700 * A242256 A189483 A164952
Adjacent sequences: A025581 A025582 A025583 * A025585 A025586 A025587


KEYWORD

nonn,easy


AUTHOR

N. J. A. Sloane.


EXTENSIONS

Better description from Vladeta Jovovic, Dec 14 2002


STATUS

approved



