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A135931
Primes whose integer square root is not a prime.
0
2, 3, 17, 19, 23, 37, 41, 43, 47, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 149, 151, 157, 163, 167, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277, 281, 283, 331, 337, 347, 349, 353, 359, 401, 409, 419, 421, 431, 433
OFFSET
1,1
COMMENTS
The integer square root of an integer x >= 0 can be defined as floor(sqrt(x)) and the remainder of this as x - (floor(sqrt(x)))^2.
PROG
(PARI) { forprime(p=2, 2000, isr = sqrtint(p); if (!isprime(isr), print1(p, ", ") ) ) }
CROSSREFS
Sequence in context: A176236 A171139 A291281 * A215323 A215351 A178437
KEYWORD
nonn
AUTHOR
Harry J. Smith, Dec 07 2007
STATUS
approved