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 A136364 a(n) = Sum_{ composite k, 1 <= k <= 10^n} (Number of divisors d of k with 1 < d < k). 1
 8, 283, 5070, 73669, 966751, 11970035, 142725365, 1657511569, 18877697635, 211802823221, 2348286736298, 25785452449087, 280880375389758, 3039062263181055, 32693207724724247, 349957928177109417 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS FORMULA a(n) = A057494(n) - 2*10^n + 1 [From Max Alekseyev, May 10 2009] EXAMPLE a(1)=8 because there are 8 distinct divisors of composite numbers k through 10^1; these are for 4(1); 6(2); 8(2); 9(1); 10(2); and 1+2+2+1+2=8. CROSSREFS Cf. A136363. Sequence in context: A226346 A217488 A247484 * A089670 A221612 A060355 Adjacent sequences:  A136361 A136362 A136363 * A136365 A136366 A136367 KEYWORD easy,nonn AUTHOR Enoch Haga, Dec 26 2007, Dec 29 2007 EXTENSIONS Edited by N. J. A. Sloane, Jan 12 2008 Three more terms from Max Alekseyev, May 10 2009 a(10) onward from Max Alekseyev, Jan 25 2010 STATUS approved

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Last modified January 23 03:08 EST 2019. Contains 319370 sequences. (Running on oeis4.)