OFFSET
1,1
COMMENTS
k*p(n)#-p(n+1) is the greatest prime < k*p(n)#-p(n+1)-1 and if k*p(n)#-p(n+1)-1 is not prime it is the greatest prime < k*p(n)#-p(n+1). Values for k are given in A090189.
EXAMPLE
1*2*3*5*7*11*13-17=30013, 1*p(6)#-p(7)=30013, 1 is the least k for n=6
30013 is prime P for n=6.
PROG
(PARI) a(n)=my(P=prod(i=1, n, prime(i)), q=prime(n+1), k); while(!ispseudoprime(P*k++ - q), ); k*P-q \\ Charles R Greathouse IV, Feb 07 2013
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Pierre CAMI, Jan 21 2004
EXTENSIONS
a(14) corrected by Charles R Greathouse IV, Feb 07 2013
STATUS
approved