A210477 - OEIS

%I #12 Aug 22 2019 18:01:53

%S 667,1147,2491,3127,4087,5767,7387,17947,23707,25591,28891,30967,

%T 55687,64507,67591,70747,75067,111547,126727,136891,141367,148987,

%U 190087,198907,256027,295927,313591,320347,329467,348091,355207,364807,372091,422491,430327,462391,532891

%N Product of adjacent primes with a gap of 6.

%C Subsequence of A111192.

%C Sum_{n>=1} 1/a(n) > 0.00405067912.

%H Harvey P. Dale, <a href="/A210477/b210477.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) = A031924(n)*(A031924(n)+6).

%p A210477 := proc(n)

%p     A031924(n)*(A031924(n)+6) ;

%p end proc:

%p seq(A210477(n),n=1..100) ; # _R. J. Mathar_, Jan 23 2013

%t Times@@@Select[Partition[Prime[Range[200]],2,1],#[[2]]-#[[1]]==6&] (* _Harvey P. Dale_, Aug 22 2019 *)

%K nonn

%O 1,1

%A _R. J. Mathar_, Jan 23 2013