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A124225 Numbers n such that the sum of the first n primes is prime as well as the sum of the squares of the first n primes is prime. 1
2, 158, 192, 216, 356, 426, 548, 680, 1178, 1196, 1466, 1500, 1524, 2324, 2438, 2904, 2990, 3060, 3146, 3618, 3902, 4110, 4134, 4346, 4602, 5790, 5840, 6186, 6344, 6710, 6720, 6836, 6990, 7592, 7632, 7716, 7790, 7838, 8156, 8420, 8622, 8658, 8664, 9092 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

PROG

(MAGMA) a013916:=func<n|IsPrime(&+[NthPrime(k): k in [1..n]])>; a098561:=func<n|IsPrime(&+[NthPrime(k)^2: k in [1..n]])>; [n: n in [1..10000]|a013916(n) and a098561(n)];  // Bruno Berselli, Dec 28 2011

(PARI) s=0; t=0; n=0; forprime(p=2, 1e6, s+=p; t+=p^2; n++; if(isprime(t)&&isprime(s), print1(n", "))) \\ Charles R Greathouse IV, Dec 28 2011

CROSSREFS

Intersection of A098561 (Numbers n such that the sum of the squares of the first n primes is prime) and A013916 (Numbers n such that the sum of the first n primes is prime).

Sequence in context: A142006 A233575 A233263 * A159030 A064071 A116638

Adjacent sequences:  A124222 A124223 A124224 * A124226 A124227 A124228

KEYWORD

nonn

AUTHOR

Tanya Khovanova, Dec 13 2006

EXTENSIONS

More terms from Bruno Berselli, Dec 28 2011

STATUS

approved

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Last modified June 24 16:32 EDT 2017. Contains 288707 sequences.