A141237 Sequence of k such that starting with P(0)=19 then k(n)*P(n-1)*(k(n)*P(n-1)-1)-1 is the least prime = P(n).

3, 1, 9, 14, 123, 39, 39, 549, 96, 701

Offset

1,1

Links

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

Example

1*19*(1*19-1)-1=341 composite
2*19*(2*19-1)-1=1405 composite
3*19*(3*19-1)-1=3191 prime so k(1)=3 P(1)=3191

Prog

(PARI) P=19; 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: A157383 A232598 A174510 * A318391 A157399 A288852

Adjacent sequences: A141234 A141235 A141236 * A141238 A141239 A141240

Keyword

nonn

Author

Pierre CAMI, Jun 16 2008

Extensions

a(9)-a(10) from Charles R Greathouse IV, Dec 27 2011

Status

approved