a(1) = 4, a(n+1) = smallest multiple of a(n) using only composite digits (4,6,8,9,0) and which is not divisible by 10.

A078236

a(1) = 4, a(n+1) = smallest multiple of a(n) using only composite digits (4,6,8,9,0) and which is not divisible by 10.

Terms

    a(0) =4a(1) =8a(2) =48a(3) =96a(4) =864a(5) =6048a(6) =489888a(7) =460984608

External references