Exactly 1 digit from {1,2,3,4,5,6,7,8,9} can precede a(n) to form a lucky number.

Terms

a(0) =13a(1) =25a(2) =43a(3) =49a(4) =53a(5) =71a(6) =103a(7) =113a(8) =125a(9) =137a(10) =141a(11) =145a(12) =149a(13) =155a(14) =157a(15) =159a(16) =165a(17) =193a(18) =199a(19) =219a(20) =239a(21) =255a(22) =267a(23) =275a(24) =287a(25) =295a(26) =297a(27) =307a(28) =313a(29) =317