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A002261 Numbers n such that 11*2^n+1 is prime.
(Formerly M2425 N0960)
2
1, 3, 5, 7, 19, 21, 43, 81, 125, 127, 209, 211, 3225, 4543, 10179, 15329, 18759, 28277, 93279, 105741 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

REFERENCES

H. Riesel, ``Prime numbers and computer methods for factorization,'' Progress in Mathematics, Vol. 57, Birkhauser, Boston, 1985, Chap. 4, see pp. 381-384.

R. M. Robinson, A report on primes of the form k.2^n+1 and on factors of Fermat numbers, Proc. Amer. Math. Soc., 9 (1958), 673-681.

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

Ray Ballinger, Proth Search Page

Ray Ballinger and Wilfrid Keller, List of primes k.2^n + 1 for k < 300

Y. Gallot, Proth.exe: Windows Program for Finding Large Primes

Wilfrid Keller, List of primes k.2^n - 1 for k < 300

Index entries for sequences of n such that k*2^n-1 (or k*2^n+1) is prime

CROSSREFS

Sequence in context: A112986 A052333 A074106 * A154524 A184805 A079131

Adjacent sequences:  A002258 A002259 A002260 * A002262 A002263 A002264

KEYWORD

hard,nonn

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com).

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Last modified February 17 06:10 EST 2012. Contains 205988 sequences.