a(1) = 5; for n > 1, a(n) is the square root of the smallest square > a(n-1)^2 with a(n-1)^2 forming its final digits.

A065780

a(1) = 5; for n > 1, a(n) is the square root of the smallest square > a(n-1)^2 with a(n-1)^2 forming its final digits.

Terms

    a(0) =5a(1) =15a(2) =35a(3) =285a(4) =4035a(5) =2660285a(6) =40530004035

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