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A100359 Numbers n such that 2^n+n+1 is prime. 5
0, 2, 6, 236, 1884, 51380, 75764 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(8) > 500000. - Robert Price, May 24 2014

LINKS

Table of n, a(n) for n=1..7.

FORMULA

a(n) = A061422(n) - 1.

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}

PROG

(PARI) is(n)=ispseudoprime(2^n+n+1) \\ Charles R Greathouse IV, Feb 20 2017

CROSSREFS

Cf. A001580, A069539, A052007, A048744, A100357, A100358.

Sequence in context: A158682 A201626 A332692 * A206033 A181772 A183398

Adjacent sequences:  A100356 A100357 A100358 * A100360 A100361 A100362

KEYWORD

hard,more,nonn

AUTHOR

Labos Elemer, Nov 19 2004

EXTENSIONS

New term 51380 from A061422 Max Alekseyev, Feb 08 2009

a(7) from Giovanni Resta, Mar 19 2014

STATUS

approved

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Last modified September 27 15:21 EDT 2020. Contains 337383 sequences. (Running on oeis4.)