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A013916 Numbers n such that the sum of the first n primes is prime. 30
1, 2, 4, 6, 12, 14, 60, 64, 96, 100, 102, 108, 114, 122, 124, 130, 132, 146, 152, 158, 162, 178, 192, 198, 204, 206, 208, 214, 216, 296, 308, 326, 328, 330, 332, 334, 342, 350, 356, 358, 426, 446, 458, 460, 464, 480, 484, 488, 512, 530, 536, 548, 568, 620, 630, 676, 680 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

David W. Wilson, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = A000720(A013917(n))

MAPLE

p:=proc(n) if isprime(sum(ithprime(k), k=1..n))=true then n else fi end: seq(p(n), n=1..690); # Emeric Deutsch

MATHEMATICA

s = 0; Do[s = s + Prime[n]; If[PrimeQ[s], Print[n]], {n, 1, 1000}]

Flatten[Position[Accumulate[Prime[Range[2000]]], _?(PrimeQ[#] &)]] (* Harvey P. Dale, Dec 16 2010 *)

Flatten[Position[PrimeQ[Accumulate[Prime[Range[2000]]]], True]] (* Fred Patrick Doty, Aug 15 2017 *)

PROG

(PARI) isA013916(n) = isprime(sum(i=1, n, prime(i))) \\ Michael B. Porter, Jan 29 2010

CROSSREFS

Cf. A007504, A013917, A013918.

Sequence in context: A015636 A015663 A057830 * A141113 A255001 A050584

Adjacent sequences:  A013913 A013914 A013915 * A013917 A013918 A013919

KEYWORD

nonn,nice,changed

AUTHOR

N. J. A. Sloane, Renaud Lifchitz (100637.64(AT)CompuServe.COM)

EXTENSIONS

More terms from David W. Wilson

STATUS

approved

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Last modified August 18 22:06 EDT 2017. Contains 290768 sequences.