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A001774
Numbers k such that 17*2^k - 1 is prime.
(Formerly M1028 N0387)
3
2, 4, 6, 16, 20, 36, 54, 60, 96, 124, 150, 252, 356, 460, 612, 654, 664, 698, 702, 972, 1188, 1312, 3062, 4214, 4288, 5280, 9100, 20262, 21676, 24828, 46144, 62148, 79974, 117784, 211464, 310744, 310754, 429318, 601158, 605394
OFFSET
1,1
REFERENCES
H. Riesel, "Prime numbers and computer methods for factorization", Progress in Mathematics, Vol. 57, Birkhäuser, Boston, 1985, Chap. 4, see pp. 381-384.
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 and Wilfrid Keller, List of primes k.2^n + 1 for k < 300
R. K. Guy, The strong law of small numbers. Amer. Math. Monthly 95 (1988), no. 8, 697-712. [Annotated scanned copy]
H. C. Williams and C. R. Zarnke, A report on prime numbers of the forms M = (6a+1)*2^(2m-1)-1 and (6a-1)*2^(2m)-1, Math. Comp., 22 (1968), 420-422.
CROSSREFS
Sequence in context: A000068 A067662 A248334 * A053285 A286850 A228119
KEYWORD
hard,nonn
EXTENSIONS
More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 02 2008
STATUS
approved