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A138580 Numbers n such that 2^(2*n-13)-13 is prime. 0
7, 8, 9, 11, 13, 15, 35, 59, 75 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..9.

EXAMPLE

2^(2*11-13)-13=499, 2^(2*13-13)-13=8179, 2^(2*15-13)-13=131059, ...

MATHEMATICA

q=13; For[i=q, i<=q, a={}; Do[x=2^(2*n-i)-i; If[PrimeQ[x], AppendTo[a, n]], {n, 10^2}]; Print["2^(2*n-", i, ")-", i, " ", a]; i=i+2]

PROG

(PARI) is(n)=isprime(2^(2*n-13)-13) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Sequence in context: A196040 A196043 A030569 * A192050 A045158 A074328

Adjacent sequences:  A138577 A138578 A138579 * A138581 A138582 A138583

KEYWORD

nonn,easy

AUTHOR

Vladimir Joseph Stephan Orlovsky, May 13 2008

STATUS

approved

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Last modified January 23 07:07 EST 2020. Contains 331168 sequences. (Running on oeis4.)