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A073435 Smallest x such that remainder if x-th composite is divided by pi(x) equals n.

%I A073435 #15 May 21 2020 21:18:11
%S A073435 4,7,8,13,30,17,35,23,40,50,53,51,55,52,63,60,68,69,146,76,154,83,156,
%T A073435 162,172,177,185,109,195,187,192,188,189,190,208,209,210,214,215,216,
%U A073435 217,230,218,219,220,224,225,251,248,249,250,255,256,262,267,280,289
%N A073435 Smallest x such that remainder if x-th composite is divided by pi(x) equals n.
%H A073435 Robert Israel, <a href="/A073435/b073435.txt">Table of n, a(n) for n = 1..10000</a>
%F A073435 a(n) = Min{x; Mod[A002808(x), A000720(x)]=n} = Min{x; A065861(x)=n}.
%e A073435 Remainder=4 appears first as Mod[c[13],Pi[13]]=Mod[22,6]=4, so a(4)=13.
%p A073435 N:= 100: m:= 1: V:= Vector(N): count:= 0:
%p A073435 for n from 6 while count < N do
%p A073435   if not isprime(n) then
%p A073435     m:= m+1;
%p A073435     t:= n mod numtheory:-pi(m);
%p A073435     if t > 0 and t <= N and V[t] = 0 then
%p A073435       count:= count+1; V[t]:= m
%p A073435     fi
%p A073435   fi
%p A073435 od:
%p A073435 convert(V,list); # _Robert Israel_, May 21 2020
%Y A073435 Cf. A000720, A002808, A065861.
%K A073435 nonn,look
%O A073435 1,1
%A A073435 _Labos Elemer_, Jul 31 2002