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%I #8 Sep 24 2019 03:02:37
%S 3,2,15,8,11,70,271,429,189,109
%N Sequence of k such that starting with P(0)=13 then k(n)*P(n-1)*(k(n)*P(n-1)-1)-1 is the least prime = P(n).
%e 1*13*(1*13-1)-1=155 composite,
%e 2*13*(2*13-1)-1=649 composite,
%e 3*13*(3*13-1)-1=1481 prime so a(1)=3 and P(1)=1481.
%o (PARI) P=13; for(i=1, 20, k=0; while(!ispseudoprime(t=k++*P*(k*P-1)-1), ); P=t; print1(k", ")) \\ _Michel Marcus_, Sep 24 2019
%Y Cf. A141233, A141234, A141236, A141237, A141238, A141239, A141240.
%K nonn,more
%O 1,1
%A _Pierre CAMI_, Jun 16 2008
%E a(9)-a(10) from _Michel Marcus_, Sep 24 2019