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 A153357 Numbers n such that the Wolstenholme number A001008(n) is a semiprime. 0
 4, 6, 11, 14, 15, 17, 19, 20, 23, 25, 31, 33, 34, 35, 37, 39, 49, 53, 55, 59, 61, 68, 90, 93, 94, 101, 116, 117, 121, 124, 145, 155, 158, 163, 169, 170, 186, 193, 194, 199, 205, 211, 214, 245, 258, 259, 264, 267, 283, 311, 315, 328, 340, 347, 359, 365 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 REFERENCES R. L. Graham, D. E. Knuth and O. Patashnik, Concrete Mathematics. Addison-Wesley, Reading, MA, 1990, p. 259. G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers. 3rd ed., Oxford Univ. Press, 1954, page 347. D. E. Knuth, The Art of Computer Programming. Addison-Wesley, Reading, MA, Vol. 1, p. 615 LINKS Hisanori Mishima, Wolstenholme number (n = 1 to 100, n = 101 to 200, n = 201 to 300, n = 301 to 400, n = 401 to 500, n = 501 to 600). Eric Weisstein's World of Mathematics, Wolstenholme's Theorem, Harmonic Number. CROSSREFS Cf. A001008 = Wolstenholme numbers: numerator of harmonic number H(n)=Sum_{i=1..n} 1/i. Cf. A002805, A056903, A067657. Sequence in context: A247336 A158138 A096833 * A310591 A002732 A144065 Adjacent sequences:  A153354 A153355 A153356 * A153358 A153359 A153360 KEYWORD hard,nonn AUTHOR Alexander Adamchuk, Dec 24 2008 EXTENSIONS More terms from Sean A. Irvine, Aug 22 2011 Two missing terms added by D. S. McNeil, Aug 23 2011 More terms from Sean A. Irvine, Apr 01 2013 STATUS approved

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Last modified August 24 02:32 EDT 2019. Contains 326260 sequences. (Running on oeis4.)