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A138577 Numbers n such that 2^(2*n-3)-3 is prime. 0
3, 4, 6, 16, 108, 112, 118, 274, 346, 1162, 1620 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..11.

EXAMPLE

2^(2*3-3)-3=5, 2^(2*4-3)-3=29, 2^(2*6-3)-3=509,...

MATHEMATICA

q=3; 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]

Select[Range[400], PrimeQ[2^(2#-3)-3]&] (* Harvey P. Dale, Aug 10 2017 *)

PROG

(PARI) is(n)=isprime(2^(2*n-3)-3) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Sequence in context: A092933 A122849 A068573 * A298149 A136242 A066732

Adjacent sequences:  A138574 A138575 A138576 * A138578 A138579 A138580

KEYWORD

nonn,easy

AUTHOR

Vladimir Joseph Stephan Orlovsky, May 13 2008

EXTENSIONS

More terms from Harvey P. Dale, Aug 10 2017

STATUS

approved

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Last modified January 24 07:18 EST 2020. Contains 331189 sequences. (Running on oeis4.)