This site is supported by donations to The OEIS Foundation.



Annual Appeal: Please make a donation to keep the OEIS running. In 2018 we replaced the server with a faster one, added 20000 new sequences, and reached 7000 citations (often saying "discovered thanks to the OEIS").
Other ways to donate

(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A131497 Values of n such that n^e starts with the digits n. 1


%S 1,4,15,56,213,813,3104,9632089,36787239,140499215,2049402728,

%T 7827156489,29893772401,6360445726168,24292055125871,354337952833519,

%U 5168578128432327,19740029272114749,4200051540382303047,16040995858310522148,233983234616956426935,893637628328498285466,3413014663516027432461

%N Values of n such that n^e starts with the digits n.

%C Subsequence of ceil(10^(k/(e-1))). - _Max Alekseyev_, Sep 08 2013

%H Max Alekseyev, <a href="/A131497/b131497.txt">Table of n, a(n) for n = 1..400</a>

%e 213 is a term of this sequence because 213^e = 2133987.96483717..., which starts with 213.

%o (PARI) e=exp(1);s=1;for(i=1,50000,s=i^e; while(s-i>11,s=s/10); if(floor(s)==i,printp1(i,", "),))

%Y Cf. A131494, A131496

%K nonn,base

%O 1,2

%A _Randy L. Ekl_, Aug 12 2007

%E 3 more terms from _Ryan Propper_, Dec 30 2007

%E a(11)-a(14) from _Donovan Johnson_, Oct 29 2010

%E Terms a(15) onward from _Max Alekseyev_, Sep 08 2013

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 12 00:07 EST 2018. Contains 318052 sequences. (Running on oeis4.)