a(1) = 1, a(n+1) is the smallest odd multiple of a(n) (other than a(n) itself) in which the digits are alternately even and odd.

A078226

a(1) = 1, a(n+1) is the smallest odd multiple of a(n) (other than a(n) itself) in which the digits are alternately even and odd.

Terms

    a(0) =1a(1) =3a(2) =9a(3) =27a(4) =81a(5) =567a(6) =8505a(7) =76545a(8) =9874305a(9) =6763898925

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