A195138 - OEIS

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A195138

First digit to appear n times in the decimal expansion of e.

2, 2, 8, 8, 2, 2, 2, 2, 9, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 2, 2, 2, 2, 2, 2, 2, 3, 9, 9, 2, 7, 4, 4, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

The digits 0 and 5 do not appear among the first 30000 terms. When do they first appear? - Jianing Song, Apr 01 2021

LINKS

Alois P. Heinz, Table of n, a(n) for n = 1..10000

EXAMPLE

From Michael De Vlieger, Sep 10 2017: (Start)

a(n) is the first decimal digit of e that first appears n times when e is expanded to the -m place:

n a(n) m

1 2 0

2 2 4

3 8 7

4 8 9

5 2 22

6 2 30

7 2 33

8 2 40

9 9 58

10 7 63

11 7 64

12 7 68

13 7 78

14 7 83

15 7 89

16 7 99

(End)

MATHEMATICA

With[{e = First@ RealDigits[N[E, 10^4]]}, Function[t, -1 + Map[FirstPosition[t, #] &, Range@ Max@ t][[All, -1]]]@ Table[BinCounts[Take[e, n], {0, 10, 1}], {n, 10^3}]] (* Michael De Vlieger, Sep 10 2017 *)

CROSSREFS

Cf. A001113, A195844, A277270, A290643, A290644.

Cf. A096567, A195139, A195141, A280811, A341438.

Sequence in context: A095297 A269545 A258983 * A094887 A021441 A196066

Adjacent sequences: A195135 A195136 A195137 * A195139 A195140 A195141

KEYWORD

nonn,base

AUTHOR

Omar E. Pol, Oct 22 2011

EXTENSIONS

More terms from D. S. McNeil, Oct 22 2011

STATUS

approved