%I #12 Oct 30 2019 04:45:35

%S 7,18718,343,125204947,231012215,11298657013,211066659013,

%T 117088913464607,2846847905744815,108244538579770418,

%U 2080795357577501075,18312871825384462928,26268977180287044053417,1734582041294009627423816

%N Smallest solution to GCD(x,A004086(x))=7^n.

%F a(n) = A069554(7^n).

%t See A071686.

%Y Cf. A004086, A055483, A069554, A071686, A072005, A072021.

%K nonn,base,more

%O 1,1

%A _Labos Elemer_, Jun 10 2002

%E a(8)-a(9) from _Max Alekseyev_, Jun 17 2011

%E a(10)-a(14) from _Giovanni Resta_, Oct 30 2019