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A228102 Numbers n such that sum of all primes <=n is prime. 2
2, 3, 4, 7, 8, 9, 10, 13, 14, 15, 16, 37, 38, 39, 40, 43, 44, 45, 46, 281, 282, 311, 312, 503, 504, 505, 506, 507, 508, 541, 542, 543, 544, 545, 546, 557, 558, 559, 560, 561, 562, 593, 594, 595, 596, 597, 598, 619, 620, 621, 622, 623, 624, 625 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Numbers n such that A034387(n) is prime.

LINKS

Jayanta Basu, Table of n, a(n) for n = 1..1000

EXAMPLE

8 is in the sequence since 2+3+5+7=17 is prime.

MATHEMATICA

t = {}; s = 0; Do[If[PrimeQ[n], s += n]; If[PrimeQ[s], AppendTo[t, n]], {n, 625}]; t

PROG

(MAGMA) [n: n in [1..700] | IsPrime(s) where s is &+PrimesUpTo(n)]; // Bruno Berselli, Aug 10 2013

CROSSREFS

Cf. A034387.

Sequence in context: A031477 A047227 A317047 * A261412 A112965 A152979

Adjacent sequences:  A228099 A228100 A228101 * A228103 A228104 A228105

KEYWORD

nonn

AUTHOR

Jayanta Basu, Aug 10 2013

STATUS

approved

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Last modified December 12 22:06 EST 2019. Contains 329963 sequences. (Running on oeis4.)