1,2

No other terms below 10^41.

The sequence is probably finite.

Table of n, a(n) for n=1..24.

Eric Weisstein's World of Mathematics, Square Number.

Cf. A016069, A016070, A018885.

Sequence in context: A068867 A111704 A052041 * A050749 A096599 A016073

Adjacent sequences: A018881 A018882 A018883 * A018885 A018886 A018887

nonn,base,more,hard

David W. Wilson

approved