A115649 Numbers whose square is the sum of distinct double factorials (A006882).

1, 2, 3, 4, 5, 7, 8, 11, 13, 20, 21, 31, 38, 62, 63, 65, 66, 70, 72, 102, 107, 109, 120, 125, 217, 218, 238, 240, 373, 382, 387, 427, 439, 834, 840, 890, 915, 1440, 1474, 1638, 1650, 3213, 3220, 3241, 3332, 3540, 5886, 6751, 6855, 13730, 14078, 14911