Numbers k such that (k!! + (k+1)!! + 1)/2 is prime.

Terms

a(0) =1a(1) =2a(2) =9a(3) =15a(4) =16a(5) =17a(6) =25a(7) =64a(8) =65a(9) =88a(10) =113a(11) =135a(12) =161a(13) =225a(14) =783a(15) =967a(16) =5135a(17) =9064a(18) =10566a(19) =15464