The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A322722

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Number of times the digit 7 appears in the first 10^n decimal digits of Euler's number e = exp(1), counting starts after the decimal point.
(history; published version)

#8 by Bruno Berselli at Mon Apr 08 03:13:29 EDT 2019

STATUS

editing

approved

#7 by Bruno Berselli at Mon Apr 08 03:13:26 EDT 2019

MATHEMATICA

Table[Count[IntegerDigits[IntegerPart[(E - 2)*10^10^n]], 7], {n, 7}] (* _Robert Price_, Apr 07 2019 *)

7}] (* Robert Price, Apr 07 2019 *)

STATUS

proposed

editing

#6 by Robert Price at Sun Apr 07 18:08:11 EDT 2019

STATUS

editing

proposed

#5 by Robert Price at Sun Apr 07 18:08:09 EDT 2019

MATHEMATICA

Table[Count[IntegerDigits[IntegerPart[(E - 2)*10^10^n]], 7], {n,

7}] (* Robert Price, Apr 07 2019 *)

STATUS

approved

editing

#4 by N. J. A. Sloane at Mon Dec 24 11:06:47 EST 2018

STATUS

proposed

approved

#3 by Martin Renner at Mon Dec 24 10:53:53 EST 2018

STATUS

editing

proposed

#2 by Martin Renner at Mon Dec 24 10:48:05 EST 2018

NAME

allocated for Martin RennerNumber of times the digit 7 appears in the first 10^n decimal digits of Euler's number e = exp(1), counting starts after the decimal point.

DATA

1, 16, 99, 1008, 9875, 99910, 1000813, 9998342, 99997536, 1000013049

OFFSET

1,2

COMMENTS

It is not known if e is normal, but the distribution of decimal digits found for the first 10^n digits of e shows no statistically significant departure from a uniform distribution.

LINKS

Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/eDigits.html">e Digits</a>.

MAPLE

a:=proc(n)

local digits, EXP1, C, i;

digits:=10^n+100;

EXP1:=convert(frac(evalf[digits](exp(1))), string)[2..digits-99];

C:=0;

for i from 1 to length(EXP1) do

if EXP1[i]="7" then C:=C+1; fi;

od;

return(C);

end;

CROSSREFS

Cf. A001113, A099298, A322648, A322715, A322716, A322717, A322718, A322719, A322720, A322721, A322723, A322724.

KEYWORD

allocated

nonn,base,more

AUTHOR

Martin Renner, Dec 24 2018

STATUS

approved

editing

#1 by Martin Renner at Mon Dec 24 10:27:44 EST 2018

NAME

allocated for Martin Renner

KEYWORD

allocated

STATUS

approved