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A124225
Numbers n such that the sum of the first n primes is prime and the sum of the squares of the first n primes is also prime.
3
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
OFFSET
1,1
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
G. L. Honaker, Jr. and Chris Caldwell, Prime Curios! 3618
Carlos Rivera, Puzzle 978. Improve this curio, Prime Puzzles and Problems Connection.
MATHEMATICA
With[{nn=9100}, Position[Thread[{Accumulate[Prime[Range[nn]]], Accumulate[ Prime[ Range[ nn]]^2]}], _?(PrimeQ[ #[[1]]]&&PrimeQ[#[[2]]]&), 1, Heads-> False]]//Flatten (* Harvey P. Dale, Aug 18 2020 *)
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
KEYWORD
nonn
AUTHOR
Tanya Khovanova, Dec 13 2006
EXTENSIONS
More terms from Bruno Berselli, Dec 28 2011
Definition rephrased by Harvey P. Dale, Aug 18 2020
STATUS
approved