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A252043 a(n) is the concatenation of first n terms of A033307. 1
1, 12, 123, 1234, 12345, 123456, 1234567, 12345678, 123456789, 1234567891, 12345678910, 123456789101, 1234567891011, 12345678910111, 123456789101112, 1234567891011121, 12345678910111213, 123456789101112131, 1234567891011121314 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

FORMULA

a(n) = floor(C*10^n) with C the Champernowne constant, 0.123456789101112131415..., A033307.

a(n) = floor(A007908(n)/10^n) For n>=10.

EXAMPLE

a(3)=123.

MAPLE

a[0]:= 0;

count:= 0:

for x from 1 to 30 do

  L:= convert(x, base, 10);

  for i from 1 to nops(L) do

    count:= count+1;

    a[count]:= a[count-1]*10+L[-i];

  od

od:

seq(a[i], i=1..count); # Robert Israel, Jan 11 2015

MATHEMATICA

b[1] = 1

b[n_] := b[n - 1]*10^(Floor[Log[10, 10n]]) + n

Table[Floor[b[n] /10^(n)], {n, 10, 200}]

Module[{nn=20, ch}, ch=RealDigits[ChampernowneNumber[], 10, nn][[1]]; Table[ FromDigits[ Take[ch, n]], {n, nn}]] (* Harvey P. Dale, Aug 31 2015 *)

CROSSREFS

Cf. A007908 (concatenate 1 through n), A033307.

Sequence in context: A037610 A035239 A057137 * A014824 A060555 A138957

Adjacent sequences:  A252040 A252041 A252042 * A252044 A252045 A252046

KEYWORD

nonn,base

AUTHOR

José de Jesús Camacho Medina, Dec 15 2014

EXTENSIONS

Definition corrected by Zak Seidov, Jan 18 2015

STATUS

approved

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Last modified October 15 13:06 EDT 2019. Contains 328030 sequences. (Running on oeis4.)