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A141238
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
2, 1, 2, 37, 16, 181, 220, 273, 959, 1151
OFFSET
1,1
EXAMPLE
1*23*(1*23-1)-1=505 composite
2*23*(2*23-1)-1=2069 prime so k(1)=2 P(1)=2069
PROG
(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
CROSSREFS
KEYWORD
nonn
AUTHOR
Pierre CAMI, Jun 16 2008
EXTENSIONS
a(10) from Charles R Greathouse IV, Dec 27 2011
STATUS
approved