a(n) contains n digits (either '1' or '4') and is divisible by 2^n.

A053314

a(n) contains n digits (either '1' or '4') and is divisible by 2^n.

Terms

    a(0) =4a(1) =44a(2) =144a(3) =4144a(4) =14144a(5) =414144a(6) =1414144a(7) =41414144a(8) =441414144a(9) =1441414144a(10) =11441414144a(11) =411441414144

External references