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A092939 Index of the first occurrence of prime(n) in A092938.

%I A092939 #8 Jul 31 2020 16:42:10
%S A092939 1,2,10,8,52,18,57,36,96,40,110,249,154,328,123,288,495,125,826,343,
%T A092939 546,431,670,833,694,1555,216,1399,1195,1620,1780,3843,2920,647,7722,
%U A092939 873,7492,4485,6768,8201,7991,5178,11744,2669,16060,5809,11149,18177,5307
%N A092939 Index of the first occurrence of prime(n) in A092938.
%C A092939 Smallest k such that prime(n) = A092938(k).
%H A092939 Robert Israel, <a href="/A092939/b092939.txt">Table of n, a(n) for n = 1..149</a>
%e A092939 First occurrence of prime(6) = 13 is A092938(18), so a(6) = 18.
%p A092939 # with f as in A092938N:= ithprime(50): V:= Vector(N): count:= 0:
%p A092939 for n from 1 while count < 50 do
%p A092939   v:= f(n);
%p A092939   if v <= N and V[v]=0 then count:= count+1; V[v]:= n;
%p A092939   fi;
%p A092939 od:
%p A092939 seq(V[ithprime(i)],i=1..50); # _Robert Israel_, Jul 31 2020
%o A092939 (PARI) {v=vector(50);for(n=1,20000,k=2*prime(n);j=1;while(!isprime(k-prime(j)),j=j+1);if(j<=z&&v[j]==0,v[j]=n));for(i=1,#v,print1(v[i],","))}
%Y A092939 Cf. A092938, A092940.
%K A092939 nonn
%O A092939 1,2
%A A092939 _Amarnath Murthy_, Mar 23 2004
%E A092939 Edited and extended by _Klaus Brockhaus_, Dec 23 2006