A010350 Base-7 Armstrong or narcissistic numbers (written in base 10).

1, 2, 3, 4, 5, 6, 10, 25, 32, 45, 133, 134, 152, 250, 3190, 3222, 3612, 3613, 4183, 9286, 35411, 191334, 193393, 376889, 535069, 794376, 8094840, 10883814, 16219922, 20496270, 32469576, 34403018, 416002778, 416352977, 420197083, 725781499, 1500022495, 15705029375, 15705029376, 28700208851

Offset: 1

Author

N. J. A. Sloane

Keywords

• base
• fini
• full
• nonn

Comments

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

Links

• Joseph Myers, Table of n, a(n) for n = 1..59 (the full list of terms, from Winter)
• Eric Weisstein's World of Mathematics, Narcissistic Number
• D. T. Winter, Table of Armstrong Numbers

Crossrefs

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

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).

Programs

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

Extensions

Edited by Joseph Myers, Jun 28 2009