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A257829
The decimal representation of the average of the digits of n starts with the digits of n.
3
1, 2, 3, 4, 5, 6, 7, 8, 9, 45, 566, 1500, 2250, 3750, 18000, 383333, 4428571, 11250000, 788888888, 1000000000, 2000000000, 3000000000, 4000000000, 5000000000, 6000000000, 7000000000, 8000000000, 9000000000, 44545454545, 358333333333, 4461538461538
OFFSET
1,2
COMMENTS
The sequence is infinite since it contains all the numbers m*10^(10^k-1), for 1 <= m <= 9 and k >= 0.
LINKS
Giovanni Resta, Table of n, a(n) for n = 1..876 (terms < 10^1000)
EXAMPLE
566 is a term since the mean of its digits is (5+6+6)/3 = 17/3 and the first 3 digits of 17/3 = 5.6666... are 566. - corrected by Joseph L. Wetherell, Mar 17 2018
MATHEMATICA
(* outputs terms with at most 100 digits *) sol[nd_] := Block[{z = Range[9 nd]/nd, x}, x = FromDigits /@ First /@ RealDigits[z, 10, nd]; x[[Select[Range@ Length@x, z[[#]] == Mean@ IntegerDigits@x[[#]] &]]]]; Union@ Flatten@Array[sol, 100]
CROSSREFS
Cf. A257830.
Sequence in context: A281745 A302501 A183532 * A219327 A219326 A335205
KEYWORD
base,nonn
AUTHOR
Eric Angelini and Giovanni Resta, May 10 2015
STATUS
approved