A010351 Base-8 Armstrong or narcissistic numbers, written in base 8.

1, 2, 3, 4, 5, 6, 7, 24, 64, 134, 205, 463, 660, 661, 40663, 42710, 42711, 60007, 62047, 636703, 3352072, 3352272, 3451473, 4217603, 7755336, 16450603, 63717005, 233173324, 3115653067, 4577203604, 61777450236, 147402312024

Offset

1,2

Comments

Whenever a term ends in 0, then a(n+1) = a(n) + 1 is also a term. 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 base-8 digits of n), but here only positive numbers are considered. - M. F. Hasler, Nov 18 2019

Links

Joseph Myers, Table of n, a(n) for n = 1..62 (the full list of terms, from Winter)

Gordon L. Miller and Mary T. Whalen, Armstrong Numbers: 153 = 1^3 + 5^3 + 3^3, Fibonacci Quarterly, 30-3 (1992), 221-224.

Eric Weisstein's World of Mathematics, Narcissistic Number

D. T. Winter, Table of Armstrong Numbers (latest backup on web.archive.org from Jan. 2010; page no longer available), published not later than Aug. 2003.

Example

432 = 660_8 (= 6*8^2 + 6*8^1 + 0*8^0), and 6^3 + 6^3 + 0^3 = 432, therefore 660 is in the sequence. It's easy to see that 432 + 1 then also satisfies the equation, as for any term that is a multiple of 8. - M. F. Hasler, Nov 21 2019

Prog

(PARI) [fromdigits(digits(n, 8))|n<-A010354] \\ M. F. Hasler, Nov 18 2019

Crossrefs

Cf. A010354 (a(n) written in base 10).

In other bases: A010343 (base 4), A010345 (base 5), A010347 (base 6), A010349 (base 7), A010352 (base 9), A005188 (base 10).

Sequence in context: A342728 A153687 A142594 * A183530 A173576 A364154

Adjacent sequences: A010348 A010349 A010350 * A010352 A010353 A010354

Keyword

base,fini,full,nonn

Author

N. J. A. Sloane

Extensions

Edited by Joseph Myers, Jun 28 2009

Status

approved