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A061421 Primes of the form 2^n+n+1. 8

%I #23 Dec 15 2017 17:35:02

%S 2,7,71,

%T 110427941548649020598956093796432407239217743554726184882600387580788973

%N Primes of the form 2^n+n+1.

%C Next term is 2^1884+1884+1, with 568 digits and is too large to include. - _Emeric Deutsch_, May 13 2006

%C The Wikipedia article "Zeisel number" gives a historical connection to A051015. - _Jonathan Sondow_, Oct 17 2017

%H K. S. Brown, <a href="http://www.mathpages.com/home/kmath006/part2/part2.htm">The Sum of the Prime Factors of N (Part 2: Primes of the Form 2k-1 + k)</a>, Math Pages

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Zeisel_number">Zeisel number</a>

%p a:=proc(n) if isprime(2^n+n+1)=true then 2^n+n+1 else fi end: seq(a(n),n=0..1000); # _Emeric Deutsch_, May 13 2006

%t {ta={{0}}, tb={{0}}};Do[g=n;s=2^n+n+1; If[PrimeQ[s], Print[n];ta=Append[ta, n]; tb=Append[tb, s]], {n, 1, 10000}];{ta, tb, g} (* _Labos Elemer_, Nov 19 2004 *)

%Y Cf. A001580, A069539, A052007, A048744, A100357, A100358, A100359.

%Y Cf. A061422.

%K nonn

%O 1,1

%A _Jason Earls_, May 02 2001

%E Edited by _N. J. A. Sloane_, May 04 2007

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Last modified April 24 20:08 EDT 2024. Contains 371963 sequences. (Running on oeis4.)