A228102 Numbers n such that sum of all primes <=n is prime.

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

Offset: 1

Author

Jayanta Basu, Aug 10 2013

Keywords

• nonn

Comments

Numbers n such that A034387(n) is prime.

Examples

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

Links

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

Crossrefs

Cf. A034387.

Programs

Magma

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

Mathematica

t = {}; s = 0; Do[If[PrimeQ[n], s += n]; If[PrimeQ[s], AppendTo[t, n]], {n, 625}]; t
Position[Accumulate[Table[If[PrimeQ[n],n,0],{n,700}]],?PrimeQ]//Flatten (* _Harvey P. Dale, Apr 02 2024 *)