A053757 a(n)=a(a(n-4))+a(n-a(n-4)) if n>2 otherwise a(n)=1.

1, 1, 1, 1, 2, 3, 4, 5, 5, 6, 7, 8, 9, 10, 10, 11, 12, 13, 13, 14, 15, 15, 16, 17, 18, 19, 20, 20, 21, 22, 22, 23, 24, 25, 26, 27, 28, 29, 29, 30, 31, 31, 32, 33, 34, 34, 35, 36, 37, 38, 39, 40, 40, 41, 42, 42, 43, 44, 45, 46, 47, 47, 48, 49, 50, 50, 51, 52, 53, 54