The smallest k >= 0 that can be represented as a linear combination of 1^2, 2^2, ..., n^2 with coefficients +-1 and that cannot be represented using 1^2, 2^2, ..., m^2 with 1<=m<n.

A392127

The smallest k >= 0 that can be represented as a linear combination of 1^2, 2^2, ..., n^2 with coefficients +-1 and that cannot be represented using 1^2, 2^2, ..., m^2 with 1<=m<n.