

A077486


Largest ndigit square which leaves a square at every step if most significant digit and least significant digit are deleted until a one or twodigit square is obtained. a(2n) = 0 if no such square exists. a(2n+1) = 9*10^2n only if no nontrivial candidate exists.


2



9, 81, 841, 8649, 64009, 0, 4004001, 0, 900000000, 0, 40000400001, 0, 9000000000000, 0, 400000040000001, 0, 90000000000000000, 0, 4000000004000000001, 0, 900000000000000000000, 0, 40000000000400000000001
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