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a(n) is the smallest positive integer for which the fractional part of exp(a(n)) begins with n.
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%I #7 Dec 14 2015 08:56:46

%S 11,14,2,5,4,7,1,24,8,363,61,140,18,11,56,281,204,81,391,624,154,36,

%T 173,23,98,63,181,14,139,37,60,82,153,519,54,315,15,2,13,20,5,6,67,

%U 297,50,10,28,21,118,115,172,16,487,272,55,93,258,249,4,99,87,282,7,73,134,242

%N a(n) is the smallest positive integer for which the fractional part of exp(a(n)) begins with n.

%H Robert Israel, <a href="/A100332/b100332.txt">Table of n, a(n) for n = 1..3908</a>

%e a(1)=11 because exp(11)=59874.1... and no other 1<= k < 11 gives (exp(k)) whose fractional part starts with 1;

%e a(2)=14 because exp(14)=1202604.2...;

%e a(7)=1 because exp(1)=2.7...;

%p V:= Array(0..999):

%p count:= 0:

%p for n from 1 while count < 999 do

%p d:= floor(log10(exp(n)));

%p Digits:= d+10;

%p for m from 1 to 3 do

%p x:= floor(10^m*exp(n)) mod 10^m;

%p if x >= 10^(m-1) and V[x] = 0 then

%p count:= count+1;

%p V[x]:= n

%p fi

%p od;

%p od:

%p seq(V[i],i=1..999); # _Robert Israel_, Dec 14 2015

%Y Cf. A100322 for analogous sequence for Pi.

%K base,nonn

%O 1,1

%A Mark Hudson (mrmarkhudson(AT)hotmail.com), Nov 17 2004