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 A072370 Numbers n such that tau(n) = ln(n) + 2 * EulerGamma - 1 (rounded off), where tau(n) denotes the number of divisors of n and EulerGamma denotes the Euler-Mascheroni constant (0.5 is rounded to 0). 0
 5, 7, 25, 33, 34, 35, 38, 39, 46, 51, 55, 57, 58, 62, 65, 69, 74, 77, 81, 212, 236, 242, 243, 244, 245, 261, 268, 275, 279, 284, 292, 316, 325, 332, 333, 338, 356, 363, 369, 387, 388, 404, 412, 423, 425, 428, 436, 452, 475, 477, 507, 508, 524, 531, 539, 548 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Dirichlet proved that the average value of tau(n) is approximately ln(n) + 2 * EulerGamma - 1 (see the reference by Tattersall). REFERENCES Tattersall, J. "Elementary Number Theory in Nine Chapters". Cambridge University Press, 1999. LINKS MATHEMATICA Select[Range[10^3], DivisorSigma[0, # ] == Round[Log[ # ] + 2*EulerGamma - 1] &] CROSSREFS Sequence in context: A166660 A037374 A056717 * A057490 A057253 A003595 Adjacent sequences:  A072367 A072368 A072369 * A072371 A072372 A072373 KEYWORD nonn AUTHOR Joseph L. Pe (joseph_l_pe(AT)hotmail.com), Jul 19 2002 STATUS approved

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Last modified May 24 04:06 EDT 2013. Contains 225613 sequences.