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A065924 Numbers n such that 1/n starts with n, after excluding leading zeros. 1

%I

%S 1,3,10,100,316,1000,3162,10000,100000,1000000,10000000,100000000,

%T 316227766,1000000000,3162277660,10000000000,100000000000,

%U 1000000000000,3162277660168,10000000000000,100000000000000

%N Numbers n such that 1/n starts with n, after excluding leading zeros.

%C All the terms are either 10^k or 10^k*sqrt(10) rounded down.

%e 316 is present because 1/316 = 0.00316..

%p with(numtheory);

%p P:=proc(i)

%p local a,b,c,n;

%p for n from 1 to i do

%p a:=1/n; b:=n; c:=0; while a<1 do a:=10*a; od;

%p while b>0 do c:=c+1; b:=trunc(b/10); od;

%p a:=trunc(10^(c-1)*a); if n=a then print(n); fi;

%p od;

%p end:

%p P(100000000000); # _Paolo P. Lava_, Dec 16 2011

%K base,nonn

%O 1,2

%A Jonathan Ayres (jonathan.ayres(AT)btinternet.com), Nov 28 2001

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Last modified August 3 08:53 EDT 2020. Contains 336197 sequences. (Running on oeis4.)