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A179866 A057330 with duplicates omitted. 1
2, 1531, 16651, 15514861 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..4.

EXAMPLE

2*2-1=3,2*3-1=5,2*5-1=11;

2,3,5;

1531,3061,6121,12241,24481;

16651,33301,66601,133201,266401,532801,1065601;

15514861,31029721,62059441,124118881,248237761,496475521,992951041,1985902081;

MATHEMATICA

q=1; Reap[Do[lst={a=Prime[n]}; While[PrimeQ[a=2a-1], AppendTo[lst, a]]; If[Length[lst]>q, q=Length[lst]; Print[lst]; Sow[lst[[1]]]], {n, 10^6}]][[2, 1]]

CROSSREFS

Cf. A057330, A005382

Sequence in context: A233906 A226699 A110027 * A282999 A201242 A062585

Adjacent sequences:  A179863 A179864 A179865 * A179867 A179868 A179869

KEYWORD

nonn,more

AUTHOR

Vladimir Joseph Stephan Orlovsky, Jan 11 2011

EXTENSIONS

Edited by N. J. A. Sloane, Jan 11 2011.

STATUS

approved

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Last modified November 23 21:46 EST 2017. Contains 295141 sequences.