A253971 Prime(n) is included iff prime(n) + n^2 is also prime.
2, 3, 7, 19, 37, 43, 79, 113, 151, 163, 193, 229, 251, 281, 317, 373, 397, 433, 463, 503, 577, 757, 827, 911, 953, 997, 1069, 1123, 1321, 1399, 1423, 1481, 1657, 1693, 1747, 2029, 2143, 2267, 2311, 2473, 2503, 2551, 2593, 2687, 2753, 2791, 2917, 3313, 3323
Offset: 1
Keywords
Examples
7 is in this sequence because 7+16=23. 19 is in this sequence because 19+64=83.
Programs
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Magma
[NthPrime(n): n in [1..500] | IsPrime(NthPrime(n)+n^2)];
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Mathematica
Prime[Select[Range[500], PrimeQ[Prime[#] + #^2] &]]
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PARI
lista(nn) = forprime (n=2, nn, if (isprime(n+primepi(n)^2), print1(n, ", "))); \\ Michel Marcus, Feb 04 2015
Formula
a(n) = prime(A064711(n)). - Michel Marcus, Feb 04 2015