First differences of lucky numbers.

Terms

a(0) =2a(1) =4a(2) =2a(3) =4a(4) =2a(5) =6a(6) =4a(7) =6a(8) =2a(9) =4a(10) =6a(11) =6a(12) =2a(13) =12a(14) =4a(15) =2a(16) =4a(17) =2a(18) =4a(19) =8a(20) =6a(21) =6a(22) =6a(23) =6a(24) =4a(25) =12a(26) =2a(27) =4a(28) =2a(29) =6