a(1) = 2, a(n+1) > a(n) is the smallest multiple of a(n) using only even digits but not divisible by 10 (i.e., having no trailing zeros).

A078223

a(1) = 2, a(n+1) > a(n) is the smallest multiple of a(n) using only even digits but not divisible by 10 (i.e., having no trailing zeros).

Terms

    a(0) =2a(1) =4a(2) =8a(3) =24a(4) =48a(5) =288a(6) =864a(7) =6048a(8) =260064a(9) =26266464a(10) =40082624064

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