Fibonacci sequence beginning 1, 21.

Terms

a(0) =1a(1) =21a(2) =22a(3) =43a(4) =65a(5) =108a(6) =173a(7) =281a(8) =454a(9) =735a(10) =1189a(11) =1924a(12) =3113a(13) =5037a(14) =8150a(15) =13187a(16) =21337a(17) =34524a(18) =55861a(19) =90385a(20) =146246a(21) =236631a(22) =382877a(23) =619508a(24) =1002385a(25) =1621893a(26) =2624278a(27) =4246171a(28) =6870449a(29) =11116620