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A013917
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a(n) is prime and sum of all primes <= a(n) is prime.
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12
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2, 3, 7, 13, 37, 43, 281, 311, 503, 541, 557, 593, 619, 673, 683, 733, 743, 839, 881, 929, 953, 1061, 1163, 1213, 1249, 1277, 1283, 1307, 1321, 1949, 2029, 2161, 2203, 2213, 2237, 2243, 2297, 2357, 2393, 2411, 2957, 3137, 3251, 3257, 3301, 3413, 3461, 3491
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OFFSET
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1,1
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LINKS
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FORMULA
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MATHEMATICA
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Prime[Flatten[Position[Accumulate[Prime[Range[500]]], _?PrimeQ]]] (* Jayanta Basu, May 18 2013 *)
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PROG
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(PARI) isA013917(n) = isprime(n) && isprime(sum(i=2, n, isprime(i)*i)) \\ Michael B. Porter, Jan 29 2010
(PARI) list(lim)=my(v=List(), s); forprime(p=2, lim, if(isprime(s+=p), listput(v, p))); Vec(v) \\ Charles R Greathouse IV, Oct 19 2021
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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