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Sequence of k such that starting with P(0)=23 then k(n)*P(n-1)*(k(n)*P(n-1)-1)-1 is the least prime = P(n).
3

%I #7 May 13 2013 01:48:49

%S 2,1,2,37,16,181,220,273,959,1151

%N Sequence of k such that starting with P(0)=23 then k(n)*P(n-1)*(k(n)*P(n-1)-1)-1 is the least prime = P(n).

%e 1*23*(1*23-1)-1=505 composite

%e 2*23*(2*23-1)-1=2069 prime so k(1)=2 P(1)=2069

%o (PARI) P=23;for(i=1,20,k=0;while(!ispseudoprime(t=k++*P*(k*P-1)-1),);P=t;print1(k", ")) \\ _Charles R Greathouse IV_, Dec 27 2011

%Y Cf. A141233-A141240.

%K nonn

%O 1,1

%A _Pierre CAMI_, Jun 16 2008

%E a(10) from _Charles R Greathouse IV_, Dec 27 2011