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%I #18 Jan 01 2021 18:09:45
%S 3,4,6,275,13,19,180,182,10,274,127,24,1214,136,22,2918,308,50,490,44,
%T 9,243,65,62,902,31,54,232,296,28,890,319,30,717,25,157,1045,254,48,
%U 698,190,181,2821,498,58,2033,2312,236,450,82,154,699,286,611,1530,434,581,2780,801,17,4373,158,71
%N a(n) is the least m such that A340226(m) = 2*n.
%C 2*n*prime(a(n))-prime(a(n)-1) and 2*n*prime(a(n))-prime(a(n)+1) are prime.
%H Robert Israel, <a href="/A339675/b339675.txt">Table of n, a(n) for n = 1..600</a>
%e For n=4, A340226(275) = 8, and this is the first appearance of 8 in A340226, so a(4) = 275.
%p V:= Vector(100): count:= 0:
%p q:= 3: r:= 5:
%p for i from 3 while count < 100 do
%p p:= q; q:= r; r:= nextprime(r);
%p for k from 2 by 2 do
%p if isprime(k*q-p) and isprime(k*q-r) then break fi;
%p od;
%p v:= k/2;
%p if v <= 100 and V[v] = 0 then count:= count+1; V[v]:= i; fi
%p od:
%p convert(V,list);
%Y Cf. A340226.
%K nonn
%O 1,1
%A _J. M. Bergot_ and _Robert Israel_, Jan 01 2021
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