Proceed counterclockwise on the outer keys of a numeric keypad (i.e., 1,2,3,6,9,8,7,4): first single digits, then concatenate two digits, then three, etc.

A249182

Proceed counterclockwise on the outer keys of a numeric keypad (i.e., 1,2,3,6,9,8,7,4): first single digits, then concatenate two digits, then three, etc.

Terms

    a(0) =1a(1) =2a(2) =3a(3) =6a(4) =9a(5) =8a(6) =7a(7) =4a(8) =12a(9) =23a(10) =36a(11) =69a(12) =98a(13) =87a(14) =74a(15) =41a(16) =123a(17) =236a(18) =369a(19) =698a(20) =987a(21) =874a(22) =741a(23) =412a(24) =1236a(25) =2369a(26) =3698a(27) =6987a(28) =9874a(29) =8741

External references