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Primes in A081175.
3

%I #16 Nov 23 2015 09:56:19

%S 3,5,17,257,65537

%N Primes in A081175.

%C The 6th term is too large to include in the data section (see Example section or the b-file).

%C 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.)

%C Primes in A000330 (x=2), or in A000537 (x=3), or in A000538 (x=4), or in A000539 (x=5) etc. See A164312 for the corresponding x values.

%H N. J. A. Sloane, <a href="/A164307/b164307.txt">Table of n, a(n) for n = 1..6</a>

%e a(1) = 1^1 + 2^1 = 3.

%e a(2) = 1^2 + 2^2 = 5.

%e a(3) = 1^4 + 2^4 = 17.

%e a(4) = 1^8 + 2^8 = 257.

%e a(5) = 1^16 + 2^16 = 65537.

%e a(6) = 1^1440 + 2^1440 + 3^1440 + 4^1440 + 5^1440 = 3.287049497374559048967261852*10^1006 = 3287049497374559048967261852 ... 458593539025033893379.

%t lst={};Do[s=0;Do[If[PrimeQ[s+=n^x],AppendTo[lst,s];Print[Date[],s]],{n, 4!}],{x,7!}];lst

%Y Cf. A000215, A070592, A019434, A092506, A093179, A100270, A123599.

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Aug 12 2009

%E Edited by _R. J. Mathar_, Aug 22 2009

%E Corrected by _N. J. A. Sloane_, Nov 23 2015 at the suggestion of _Jaroslav Krizek_.