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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..10.

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

Cf. A141233-A141240.

Sequence in context: A191657 A155796 A341530 * A094690 A010249 A228005

Adjacent sequences:  A141235 A141236 A141237 * A141239 A141240 A141241

KEYWORD

nonn

AUTHOR

Pierre CAMI, Jun 16 2008

EXTENSIONS

a(10) from Charles R Greathouse IV, Dec 27 2011

STATUS

approved

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Last modified May 13 12:02 EDT 2021. Contains 343839 sequences. (Running on oeis4.)