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%I #9 Jun 18 2018 06:40:11
%S 7,8,5,4,3,1,5,9,8,7,8,0,0,5,8,3,2,4,0,6,1,5,6,6,2,9,4,8,1,3,0,3,6,1,
%T 8,4,8,4,6,1,9,2,2,1,3,3,8,6,8,7,8,8,9,0,6,5,9,6,3,5,3,0,2,4,2,3,0,9,
%U 0,5,2,1,6,0,7,0,1,9,9,4,7,5,7,9,3,4,8,6,6,3,3,1,1,4,3,3,6,6,2,4
%N 10-adic integer x such that x^3 == 3 mod 10^n for all n.
%H Kenny Lau, <a href="/A225404/b225404.txt">Table of n, a(n) for n = 1..10000</a>
%e 7^3 == 3 (mod 10).
%e 87^3 == 3 (mod 100).
%e 587^3 == 3 (mod 1000).
%e 4587^3 == 3 (mod 10000).
%e 34587^3 == 3 (mod 100000).
%e 134587^3 == 3 (mod 1000000).
%o (PARI) n=0; for(i=1, 100, m=3; for(x=0, 9, if(((n+(x*10^(i-1)))^3)%(10^i)==m, n=n+(x*10^(i-1)); print1(x", "); break)))
%o (Python) n=7;p=1;i=1;exec("print(i,n//p);i+=1;p*=10;n+=n**3//p*7%10*p;"*10000) # _Kenny Lau_, Jun 07 2018
%K nonn,base
%O 1,1
%A _Aswini Vaidyanathan_, May 07 2013