A product of consecutive doubled Fibonacci numbers.

Terms

a(0) =1a(1) =3a(2) =6a(3) =16a(4) =40a(5) =105a(6) =273a(7) =715a(8) =1870a(9) =4896a(10) =12816a(11) =33553a(12) =87841a(13) =229971a(14) =602070a(15) =1576240a(16) =4126648a(17) =10803705a(18) =28284465a(19) =74049691a(20) =193864606a(21) =507544128a(22) =1328767776a(23) =3478759201a(24) =9107509825a(25) =23843770275a(26) =62423800998a(27) =163427632720