If a, b in sequence, so is a*b+2.

Terms

a(0) =2a(1) =6a(2) =14a(3) =30a(4) =38a(5) =62a(6) =78a(7) =86a(8) =126a(9) =158a(10) =174a(11) =182a(12) =198a(13) =230a(14) =254a(15) =318a(16) =350a(17) =366a(18) =374a(19) =398a(20) =422a(21) =462a(22) =470a(23) =510a(24) =518a(25) =534a(26) =638a(27) =702a(28) =734a(29) =750