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A322722
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.
9
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, e Digits.
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;
MATHEMATICA
Table[Count[IntegerDigits[IntegerPart[(E - 2)*10^10^n]], 7], {n, 7}] (* Robert Price, Apr 07 2019 *)
KEYWORD
nonn,base,more
AUTHOR
Martin Renner, Dec 24 2018
STATUS
approved