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%I #8 Sep 13 2019 20:26:08
%S 33,8833,66644,66777,117766,118811,990000,1144000,9997777,115522333,
%T 116660044,116661111,1100088555,1100088855,1100111100,1100111111,
%U 1100111333,1100112200,1100112211,1100112222,2277334444,2277334455,2277334466,2277334477,2277335500,2288811222
%N n and pi(n) are both made of nontrivial runs of identical digits, where pi(n)=A000720(n).
%C A run of length 1 is trivial.
%C Up to 10^18 there are only 5 prime terms: 9997777, 1122991155533399, 44770077777722233, 440009996622997711, 442244499338866333. - _Giovanni Resta_, Sep 13 2019
%H Giovanni Resta, <a href="/A116056/b116056.txt">Table of n, a(n) for n = 1..418</a> (terms < 10^18)
%e pi(118811) = 11199, pi(9997777) = 664444.
%t zyQ[n_] := Min[Length /@ Split[IntegerDigits[n]]] > 1; Select[Range[10^7], zyQ[#] && zyQ[PrimePi[#]] &] (* _Giovanni Resta_, Sep 13 2019 *)
%Y Cf. A000720, A033023, A103357.
%K nonn,base
%O 1,1
%A _Giovanni Resta_, Feb 13 2006
%E More terms from _Giovanni Resta_, Sep 13 2019
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