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

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A010350 Base-7 Armstrong or narcissistic numbers (written in base 10). 15

%I #26 Jan 17 2020 14:09:39

%S 1,2,3,4,5,6,10,25,32,45,133,134,152,250,3190,3222,3612,3613,4183,

%T 9286,35411,191334,193393,376889,535069,794376,8094840,10883814,

%U 16219922,20496270,32469576,34403018,416002778,416352977,420197083,725781499,1500022495,15705029375,15705029376,28700208851

%N Base-7 Armstrong or narcissistic numbers (written in base 10).

%C Like the other single-digit terms, zero would satisfy the definition (n = Sum_{i=1..k} d[i]^k when d[1..k] are the digits of n), but here only positive numbers are considered. - _M. F. Hasler_, Nov 20 2019

%H Joseph Myers, <a href="/A010350/b010350.txt">Table of n, a(n) for n = 1..59</a> (the full list of terms, from Winter)

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/NarcissisticNumber.html">Narcissistic Number</a>

%H D. T. Winter, <a href="http://ftp.cwi.nl/dik/Armstrong">Table of Armstrong Numbers</a>

%o (PARI) select( {is_A010350(n)=n==vecsum([d^#n|d<-n=digits(n,7)])}, [0..10^6]) \\ This yields only terms < 10^6, for illustration of is_A010350(). - _M. F. Hasler_, Nov 20 2019

%Y Cf. A010349 (a(n) written in base 7).

%Y In other bases: A010344 (base 4), A010346 (base 5), A010348 (base 6), A010354 (base 8), A010353 (base 9), A005188 (base 10), A161948 (base 11), A161949 (base 12), A161950 (base 13), A161951 (base 14), A161952 (base 15), A161953 (base 16).

%K base,fini,full,nonn

%O 1,2

%A _N. J. A. Sloane_

%E Edited by _Joseph Myers_, Jun 28 2009

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.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 24 20:06 EDT 2024. Contains 371963 sequences. (Running on oeis4.)