OFFSET
1,1
COMMENTS
The 6th term is too large to include in the data section (see Example section or the b-file).
Primes of the form sum_{j=1..u} j^x for some x>0, u>1. (Since the case of x=1 leads to the triangular numbers with no additional primes, this is equivalent to the definition.)
LINKS
N. J. A. Sloane, Table of n, a(n) for n = 1..6
EXAMPLE
a(1) = 1^1 + 2^1 = 3.
a(2) = 1^2 + 2^2 = 5.
a(3) = 1^4 + 2^4 = 17.
a(4) = 1^8 + 2^8 = 257.
a(5) = 1^16 + 2^16 = 65537.
a(6) = 1^1440 + 2^1440 + 3^1440 + 4^1440 + 5^1440 = 3.287049497374559048967261852*10^1006 = 3287049497374559048967261852 ... 458593539025033893379.
MATHEMATICA
lst={}; Do[s=0; Do[If[PrimeQ[s+=n^x], AppendTo[lst, s]; Print[Date[], s]], {n, 4!}], {x, 7!}]; lst
CROSSREFS
KEYWORD
nonn
AUTHOR
Vladimir Joseph Stephan Orlovsky, Aug 12 2009
EXTENSIONS
Edited by R. J. Mathar, Aug 22 2009
Corrected by N. J. A. Sloane, Nov 23 2015 at the suggestion of Jaroslav Krizek.
STATUS
approved