A037041 Number of quadratic residues mod n for some n (A000224 sorted and duplicates removed).

1, 2, 3, 4, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 18, 19, 20, 21, 22, 23, 24, 27, 28, 30, 31, 32, 33, 34, 36, 37, 38, 40, 42, 44, 45, 46, 48, 49, 51, 52, 53, 54, 55, 56, 57, 60, 62, 63, 64, 66, 68, 69, 70, 72, 74, 75, 76, 77, 79, 80, 81, 82, 84, 87, 88, 90, 91, 92, 93, 96, 97, 98