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 A098561 Numbers n such that the sum of the squares of the first n primes is prime. 11

%I

%S 2,18,26,36,68,78,144,158,164,174,192,212,216,236,264,288,294,338,344,

%T 356,384,404,416,426,500,516,518,522,534,540,548,614,678,680,782,858,

%U 866,876,878,896,900,912,950,974,996,1064,1080,1082,1100,1122,1158,1160

%N Numbers n such that the sum of the squares of the first n primes is prime.

%C a(n) must clearly be even.

%H Zak Seidov, <a href="/A098561/b098561.txt">Table of n, a(n) for n = 1..1050</a>

%e 2 is a term as the sum of the squares of the first two primes is 2^2 + 3^2 = 13, which is prime.

%t Select[Range, PrimeQ[Sum[Prime[i]^2, {i, #}]] &] (* _Carl Najafi_, Aug 22 2011 *)

%Y Cf. A098562 (corresponding primes), A024450 (sums of squares of primes), A098563 (sums of cubes of primes), A013916 (sums of primes).

%K nonn

%O 1,1

%A _Rick L. Shepherd_, Sep 14 2004

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Last modified October 18 18:56 EDT 2019. Contains 328197 sequences. (Running on oeis4.)