Fibonacci sequence beginning 0, 12.

Terms

a(0) =0a(1) =12a(2) =12a(3) =24a(4) =36a(5) =60a(6) =96a(7) =156a(8) =252a(9) =408a(10) =660a(11) =1068a(12) =1728a(13) =2796a(14) =4524a(15) =7320a(16) =11844a(17) =19164a(18) =31008a(19) =50172a(20) =81180a(21) =131352a(22) =212532a(23) =343884a(24) =556416a(25) =900300a(26) =1456716a(27) =2357016a(28) =3813732a(29) =6170748