A004835 Numbers that are the sum of at most 6 nonzero 4-th powers.

0, 1, 2, 3, 4, 5, 6, 16, 17, 18, 19, 20, 21, 32, 33, 34, 35, 36, 48, 49, 50, 51, 64, 65, 66, 80, 81, 82, 83, 84, 85, 86, 96, 97, 98, 99, 100, 101, 113, 114, 115, 116, 129, 130, 131, 145, 146, 161, 162, 163, 164, 165, 166