The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A049010 Mean divisor of n differs by <= 1 from mean divisor of all numbers from 1 to n-1. 1
 2, 3, 4, 6, 360, 420, 480, 504, 630, 1400, 1540, 1760, 1820, 2912, 4440, 4464, 6888, 7150, 8856, 9920, 10290, 14805, 18330, 23058, 30784, 31725, 42822, 50864, 52338, 58653, 81627, 96186, 114513, 117819, 161253, 192104, 244970, 365180, 560014, 638480, 785148 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Amiram Eldar, Table of n, a(n) for n = 1..90 EXAMPLE At 161253, 10920.0-10919.87+=0.127+, which is a difference of <1. MATHEMATICA t = {1, 1}; seq = {}; Do[s = DivisorSigma[#, n] & /@ {0, 1}; If[Abs[s[[2]]/s[[1]] - t[[2]]/t[[1]]] <= 1, AppendTo[seq, n]]; t += s, {n, 2, 162000}]; seq (* Amiram Eldar, Sep 06 2019 *) CROSSREFS Cf. A000005, A000203, A048978. Sequence in context: A135236 A029962 A259388 * A340100 A361396 A021903 Adjacent sequences: A049007 A049008 A049009 * A049011 A049012 A049013 KEYWORD easy,nonn AUTHOR Enoch Haga EXTENSIONS a(1) corrected and more terms added by Amiram Eldar, Sep 06 2019 STATUS approved

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

Last modified June 13 22:21 EDT 2024. Contains 373391 sequences. (Running on oeis4.)