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A121248
Numbers k such that the sum of the first 2^k primes is a prime.
2
0, 1, 2, 6, 9, 10, 32, 36, 55
OFFSET
1,3
COMMENTS
Corresponding primes in the sums of the first 2^n primes or primes in A099825[n] are given in A113617[n] = {2,5,17,8893,868151,3875933,219554912086470964379,...}.
FORMULA
A099825(a(n)) = A113617(n). - Amiram Eldar, Jul 01 2024
MATHEMATICA
Do[f=Sum[Prime[k], {k, 1, 2^n}]; If[PrimeQ[f], Print[{n, f}]], {n, 0, 32}]
CROSSREFS
KEYWORD
nonn,hard,more
AUTHOR
Alexander Adamchuk, Aug 22 2006
EXTENSIONS
Edited by Robert G. Wilson v, Aug 26 2006
a(7)-a(9) from Amiram Eldar, Jul 01 2024
STATUS
approved