The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A180265 a(n) = smallest k such that sigma(k) = 14^n, or zero if no such k exists. 6
 1, 13, 0, 1164, 15132, 230484, 2823492, 36705396, 508541124, 7194470556, 100696385244, 1503091145388, 19540184890044, 273550891167372, 3811871194625676, 53378900339114532, 727176010568075796, 10177815744800162004, 142523339476298463228, 1994910930816765350844, 27918212600229725023068 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS Max Alekseyev, Table of n, a(n) for n = 0..100 EXAMPLE a(0)=1 since sigma(1)=14^0=1. a(1)=13 since sigma(13)=14. a(2)=0 since no N exists such that sigma(N)=14^2. a(6)=2823492=2^2*3*7*33613 since sigma(2823492)=14^6 is the first 6th power. a(7)=36705396=2^2*3*7*13*33613 since sigma(36705396)=14^7 is the first 7th power. CROSSREFS Cf. A046528, A048251, A110077, A180460, A180461, A180462, A180463, A180464 Sequence in context: A094902 A252056 A096069 * A165400 A181154 A367303 Adjacent sequences: A180262 A180263 A180264 * A180266 A180267 A180268 KEYWORD nonn AUTHOR Walter Kehowski, Aug 22 2010 EXTENSIONS Edited (including b-file) by N. J. A. Sloane, Oct 05 2010 Terms a(25) onward from Max Alekseyev, Mar 04 2014 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 July 24 22:37 EDT 2024. Contains 374585 sequences. (Running on oeis4.)