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A253971
Prime(n) is included iff prime(n) + n^2 is also prime.
1
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
1,1
FORMULA
a(n) = prime(A064711(n)). - Michel Marcus, Feb 04 2015
EXAMPLE
7 is in this sequence because 7+16=23.
19 is in this sequence because 19+64=83.
MATHEMATICA
Prime[Select[Range[500], PrimeQ[Prime[#] + #^2] &]]
PROG
(Magma) [NthPrime(n): n in [1..500] | IsPrime(NthPrime(n)+n^2)];
(PARI) lista(nn) = forprime (n=2, nn, if (isprime(n+primepi(n)^2), print1(n, ", "))); \\ Michel Marcus, Feb 04 2015
CROSSREFS
Sequence in context: A298943 A340281 A172461 * A291339 A235616 A257551
KEYWORD
nonn
AUTHOR
Vincenzo Librandi, Feb 04 2015
STATUS
approved