This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A092338 Number of numbers d with n mod d <= 1. 1
 1, 2, 3, 4, 4, 5, 5, 5, 6, 6, 5, 7, 7, 5, 7, 8, 6, 7, 7, 7, 9, 7, 5, 9, 10, 6, 7, 9, 7, 9, 9, 7, 9, 7, 7, 12, 10, 5, 7, 11, 9, 9, 9, 7, 11, 9, 5, 11, 12, 8, 9, 9, 7, 9, 11, 11, 11, 7, 5, 13, 13, 5, 9, 12, 10, 11, 9, 7, 9, 11, 9, 13, 13, 5, 9, 11, 9, 11, 9, 11, 14, 8, 5, 13, 15, 7, 7, 11, 9, 13 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 FORMULA G.f.: x^2/(x - 1) + ((1 + x)*(log(1 - x) + psi(1, x)))/log(x)  where psi(1,x) is the logarithmic derivative of the x-gamma function at z=1. - Olivier Gérard, Jun 24 2012 For n>1, a(n) = Sum_{i=1..n-1} floor(n/i)-floor((n-2)/i). - Wesley Ivan Hurt, Sep 13 2017 PROG (Haskell) a092338 n = length \$ filter (<= 1) \$ map (mod n) [1..n] -- Reinhard Zumkeller, Jul 04 2012 (PARI) A006218(n)=sum(k=1, sqrtint(n), n\k)*2-sqrtint(n)^2 a(n)=if(n>4, A006218(n)-A006218(n-2)-1, n) \\ Charles R Greathouse IV, Sep 13 2017 CROSSREFS Sequence in context: A070546 A034586 A268383 * A199769 A030601 A049839 Adjacent sequences:  A092335 A092336 A092337 * A092339 A092340 A092341 KEYWORD nonn,easy AUTHOR Reinhard Zumkeller, Mar 18 2004 EXTENSIONS Wrong comment removed by Reinhard Zumkeller, Jul 04 2012 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified October 22 20:36 EDT 2017. Contains 293777 sequences.