Fibonacci sequence beginning 0, 20.

Terms

a(0) =0a(1) =20a(2) =20a(3) =40a(4) =60a(5) =100a(6) =160a(7) =260a(8) =420a(9) =680a(10) =1100a(11) =1780a(12) =2880a(13) =4660a(14) =7540a(15) =12200a(16) =19740a(17) =31940a(18) =51680a(19) =83620a(20) =135300a(21) =218920a(22) =354220a(23) =573140a(24) =927360a(25) =1500500a(26) =2427860a(27) =3928360a(28) =6356220a(29) =10284580