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A010352 Base-9 Armstrong or narcissistic numbers, written in base 9. 8

%I #27 Jan 17 2020 14:08:19

%S 1,2,3,4,5,6,7,8,45,55,150,151,570,571,2446,12036,12336,14462,2225764,

%T 6275850,6275851,12742452,356614800,356614801,1033366170,1033366171,

%U 1455770342,8463825582,131057577510,131057577511

%N Base-9 Armstrong or narcissistic numbers, written in base 9.

%C From _M. F. Hasler_, Nov 18 2019: (Start)

%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 base-9 digits of n), but here only positive numbers are considered.

%C Terms a(n+1) = a(n) + 1 (n = 11, 13, 20, 23, 25, 29, 33, 48, 51, 57) correspond to solutions a(n) that are multiples of 9, in which case a(n) + 1 is also a solution. (End)

%H Joseph Myers, <a href="/A010352/b010352.txt">Table of n, a(n) for n = 1..58</a> (the full list of terms, from Winter)

%H Gordon L. Miller and Mary T. Whalen, <a href="https://www.fq.math.ca/Scanned/30-3/miller.pdf">Armstrong Numbers: 153 = 1^3 + 5^3 + 3^3</a>, Fibonacci Quarterly, 30-3 (1992), 221-224.

%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://web.archive.org/web/20100109234250/http://ftp.cwi.nl:80/dik/Armstrong">Table of Armstrong Numbers</a> (latest backup on web.archive.org from Jan. 2010; page no longer available), published not later than Aug. 2003.

%e 126 = 150_9 (= 1*9^2 + 5*9^1 + 0*9^0) = 1^3 + 5^3 + 0^3. It is easy to see that 126 + 1 then also satisfies this relation, as for all other terms that are multiples of 9. - _M. F. Hasler_, Nov 21 2019

%o (PARI) [fromdigits(digits(n,9))|n<-A010353] \\ _M. F. Hasler_, Nov 18 2019

%Y Cf. A010353 (a(n) written in base 10).

%Y In other bases: A010343 (base 4), A010345 (base 5), A010347 (base 6), A010349 (base 7), A010351 (base 8), A005188 (base 10).

%K base,fini,full,nonn

%O 1,2

%A _N. J. A. Sloane_

%E Edited by _Joseph Myers_, Jun 28 2009

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