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 A083919 Number of divisors of n that are congruent to 9 modulo 10. 11
 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 1, 0, 0, 1, 2, 0, 0, 0, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,99 LINKS FORMULA a(n) = A000005(n) - A083910(n) - A083911(n) - A083912(n) - A083913(n) - A083914(n) - A083915(n) - A083916(n) - A083917(n) - A083918(n). G.f.: Sum_{k>=1} x^(9*k)/(1 - x^(10*k)). - Ilya Gutkovskiy, Sep 11 2019 CROSSREFS Cf. A010879, A000005, A001227. Sequence in context: A102448 A102683 A122840 * A063665 A276306 A072507 Adjacent sequences:  A083916 A083917 A083918 * A083920 A083921 A083922 KEYWORD nonn AUTHOR Reinhard Zumkeller, May 08 2003 STATUS approved

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Last modified May 8 19:28 EDT 2021. Contains 343666 sequences. (Running on oeis4.)