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%I #21 Feb 12 2017 21:15:07
%S 2,5,11,19,23,31,41,47,59,71,83,97,101,103,109,113,127,137,157,163,
%T 167,173,179,191,197,223,227,229,233,239,241,263,269,271,317,337,349,
%U 353,367,389,401,409,433,439,449,457,461,463,467,491,521,563,571,607,613,617,631,641,653,661,701,709,719,739,757,797
%N Primes p such that the sum of all primes <= p has no prime divisor > p.
%C Number of terms < 10^k: 2, 12, 79, 523, 4124, 32678, 267850, etc. Compare these to A006880. - _Robert G. Wilson v_, Feb 09 2017
%C Primes p such that A006530(A007504(i)) <= p, where i is the index of p in A000040. - _Felix Fröhlich_, Feb 12 2017
%H Robert G. Wilson v, <a href="/A282246/b282246.txt">Table of n, a(n) for n = 1..10000</a>
%e 5 is in the sequence for the sum of all primes <= 5 is 10, and 10 has no prime divisor > 5.
%e 17 is not in the sequence for the corresponding sum is 58 which has a prime divisor > 17.
%t p = s = 2; lst = {}; While[p < 1000, If[ FactorInteger[s][[-1, 1]] <= p, AppendTo[lst, p]]; p = NextPrime@ p; s = s + p]; lst (* _Robert G. Wilson v_, Feb 09 2017 *)
%o (PARI) isok(n) = isprime(n) && (vecmax(factor(sum(k=1, primepi(n), prime(k)))[,1]) <= n); \\ _Michel Marcus_, Feb 12 2017
%Y Cf. A007504, A013916, A013917, A013918, A046731.
%K nonn
%O 1,1
%A _Emmanuel Vantieghem_, Feb 09 2017
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