Cumulative sum of double primorials (A079078).

Terms

a(0) =1a(1) =3a(2) =6a(3) =16a(4) =37a(5) =147a(6) =420a(7) =2290a(8) =7477a(9) =50487a(10) =200910a(11) =1534220a(12) =7099871a(13) =61765581a(14) =301088574a(15) =2870376944a(16) =15554495573a(17) =167142509403a(18) =940873745772