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A196940 Primes of the form 15*2^n - 1. 2
29, 59, 239, 479, 15359, 245759, 1966079, 32212254719, 32985348833279, 141670994486089356410879, 18133887294219437620592639, 72535549176877750482370559, 1246151246048358630847319119012823039, 638029437976759618993827388934565396479 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Primes in A196305.

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..28

MATHEMATICA

Select[Table[15 2^n - 1, {n, 1, 300}], PrimeQ] (* Vincenzo Librandi, Feb 23 2014 *)

PROG

(PARI) for(n=1, 1e3, if(ispseudoprime(t=15<<n-1), print1(t", "))) \\ Charles R Greathouse IV, Oct 08 2011

(MAGMA) [a: n in [1..130] | IsPrime(a) where a is 15*2^n-1]; // Vincenzo Librandi, Feb 23 2014

CROSSREFS

Cf. A002237 (n such that 15*2^n-1 is prime).

Sequence in context: A129813 A060229 A139507 * A104119 A042674 A078948

Adjacent sequences:  A196937 A196938 A196939 * A196941 A196942 A196943

KEYWORD

nonn

AUTHOR

Brad Clardy, Oct 07 2011

STATUS

approved

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Last modified April 26 09:52 EDT 2019. Contains 322472 sequences. (Running on oeis4.)