A358702 a(n) is the least k > 0 such that the sum of the decimal digits of k^2 is n, or 0 if no such k exists.
1, 0, 0, 2, 0, 0, 4, 0, 3, 8, 0, 0, 7, 0, 0, 13, 0, 24, 17, 0, 0, 43, 0, 0, 67, 0, 63, 134, 0, 0, 83, 0, 0, 167, 0, 264, 314, 0, 0, 313, 0, 0, 707, 0, 1374, 836, 0, 0, 1667, 0, 0, 2236, 0, 3114, 4472, 0, 0, 6833, 0, 0, 8167, 0, 8937, 16667, 0, 0, 21886, 0, 0, 29614
Offset: 1