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A195138
First digit to appear n times in the decimal expansion of e.
10
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
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
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 *)
KEYWORD
nonn,base
AUTHOR
Omar E. Pol, Oct 22 2011
EXTENSIONS
More terms from D. S. McNeil, Oct 22 2011
STATUS
approved