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A141240 Sequence of k such that starting with P(0)=31 then k(n)*P(n-1)*(k(n)*P(n-1)-1)-1 is the least prime = P(n). 7
1, 11, 4, 15, 95, 26, 87, 634, 939, 10386 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Under the Bunyakovsky conjecture, a(n) exists for every n. [Charles R Greathouse IV, Dec 27 2011]

LINKS

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

EXAMPLE

1*31*(1*31-1)-1=929 prime so k(1)=1 P(1)=929

PROG

(PARI) P=31; 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-A141239.

Sequence in context: A248175 A114267 A166205 * A298892 A038318 A010186

Adjacent sequences:  A141237 A141238 A141239 * A141241 A141242 A141243

KEYWORD

nonn

AUTHOR

Pierre CAMI, Jun 16 2008

EXTENSIONS

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

STATUS

approved

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Last modified November 13 23:01 EST 2019. Contains 329106 sequences. (Running on oeis4.)