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A061421
Primes of the form 2^n+n+1.
8
2, 7, 71, 110427941548649020598956093796432407239217743554726184882600387580788973
OFFSET
1,1
COMMENTS
Next term is 2^1884+1884+1, with 568 digits and is too large to include. - Emeric Deutsch, May 13 2006
The Wikipedia article "Zeisel number" gives a historical connection to A051015. - Jonathan Sondow, Oct 17 2017
MAPLE
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
MATHEMATICA
{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 *)
KEYWORD
nonn
AUTHOR
Jason Earls, May 02 2001
EXTENSIONS
Edited by N. J. A. Sloane, May 04 2007
STATUS
approved