%I
%S 1,1,1,5,7315048,4293861989,11387819007325752
%N a(n) = d(n)/p(n1)# where d(n) > 0 is the common difference of the smallest pterm arithmetic progression of primes beginning with p = p(n) = nth prime.
%C d(n) is the least d > 0 such that p, p+d, p+2d, ..., p+(p1)d are all prime with p = p(n), and p(n1)# = A002110(n1) is a primorial.
%C d(n) is always a multiple of p(n1)#.
%C a(5) and a(6) are due to G. Loh in 1986, and a(7) to Phil Carmody in 2001.
%C See A088430 and A231017 for more comments, references, links, and examples.
%H <a href="/index/Pri#primes_AP">Index entries for sequences related to primes in arithmetic progressions</a>
%F a(n) = A088430(n) / A002110(n) = (A231017(n)  prime(n)) / A002110(n).
%e Prime(3) = 5 and 5, 11, 17, 23, 29 is the smallest 5term AP beginning with 5, so a(3) = (115)/p(2)# = 6/2*3 = 1.
%Y Cf. A002110, A088430, A231017.
%K hard,more,nonn
%O 1,4
%A _Jonathan Sondow_, Nov 08 2013
