A010346 Base-5 Armstrong or narcissistic numbers (written in base 10).

1, 2, 3, 4, 13, 18, 28, 118, 289, 353, 419, 4890, 4891, 9113, 1874374, 338749352, 2415951874

Offset: 1

Author

N. J. A. Sloane

Keywords

• base
• fini
• full
• nonn

Comments

Zero would also satisfy the definition as the other single-digit terms, but here only positive numbers are considered. - M. F. Hasler, Nov 20 2019

Links

• Eric Weisstein's World of Mathematics, Narcissistic Number
• D. T. Winter, Table of Armstrong Numbers

Crossrefs

Cf. A010345 (a(n) written in base 5).

In other bases: A010344 (base 4), A010348 (base 6), A010350 (base 7), 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).

Programs

PARI

A010346=select( is_A010346(n)={n==vecsum([d^#n|d<-n=digits(n,5)])}, [0..9999]) \\ This yields only terms < 10^4 (i.e., all but the last 3 terms), for illustration of is_A010346(). In older versions of PARI, use {n==sum(i=1,#n=digits(n,5),n[i]^#n)}. - M. F. Hasler, Nov 20 2019

Extensions

Edited by Joseph Myers, Jun 28 2009