Lucky numbers that are decimal concatenations of n with n + 1.

Terms

a(0) =67a(1) =1011a(2) =1819a(3) =3031a(4) =4041a(5) =4647a(6) =5253a(7) =5455a(8) =6061a(9) =6667a(10) =7677a(11) =8283a(12) =114115a(13) =138139a(14) =144145a(15) =160161a(16) =162163a(17) =178179a(18) =196197a(19) =210211a(20) =214215a(21) =234235a(22) =240241a(23) =246247a(24) =252253a(25) =258259a(26) =264265a(27) =274275a(28) =306307a(29) =312313