A304493 a(0) = 1; a(n) = a(n-a(floor(n/2))) + a(n-a(floor(n/4))).

1, 2, 3, 5, 5, 8, 7, 11, 13, 12, 14, 18, 19, 20, 17, 19, 23, 24, 27, 28, 26, 31, 22, 27, 32, 34, 35, 37, 42, 46, 46, 45, 40, 40, 45, 40, 44, 48, 49, 55, 52, 56, 60, 65, 57, 64, 70, 72, 69, 70, 68, 64, 64, 67, 69, 67, 72, 71, 75, 80, 73, 79, 89, 84, 88, 94, 100, 94, 84, 96, 116, 117, 106, 116, 107, 106

Offset: 0

Author

Ilya Gutkovskiy, May 13 2018

Keywords

• nonn
• look

Links

• Robert Israel, Table of n, a(n) for n = 0..10000
• Ilya Gutkovskiy, Scatter plot of a(n) up to n=50000
• Index entries for Hofstadter-type sequences

Crossrefs

Cf. A002265, A004526, A005185, A083662, A244477.

Programs

Maple

f:= proc(n) option remember;
  procname(n-procname(floor(n/2)))+procname(n-procname(floor(n/4)))
end proc:
f(0):= 1;
map(f, [$0..100]); # Robert Israel, Dec 02 2019

Mathematica

a[n_] := a[n] = a[n - a[Floor[n/2]]] + a[n - a[Floor[n/4]]]; a[0] = 1; Table[a[n], {n, 0, 75}]