A287475 a(0) = 0; a(1) = 1; a(2*n) = a(n), a(2*n+1) = a(n-a(n)) + a(n-a(n+1)).

0, 1, 1, 0, 1, 2, 0, 1, 1, 1, 2, 2, 0, 2, 1, 0, 1, 2, 1, 2, 2, 2, 2, 3, 0, 2, 2, 2, 1, 3, 0, 1, 1, 1, 2, 1, 1, 3, 2, 4, 2, 2, 2, 4, 2, 4, 3, 5, 0, 2, 2, 6, 2, 0, 2, 4, 1, 4, 3, 5, 0, 3, 1, 0, 1, 2, 1, 2, 2, 2, 1, 4, 1, 2, 3, 3, 2, 3, 4, 4, 2, 4, 2, 8, 2, 4, 4, 6, 2, 4, 4, 4, 3, 6, 5, 7, 0, 3, 2, 10, 2

Offset

0,6

Comments

A variation on Hofstadter's Q-sequence and Stern's diatomic sequence.

Links

Table of n, a(n) for n=0..100.

Michael Gilleland, Some Self-Similar Integer Sequences

Eric Weisstein's World of Mathematics, Stern's Diatomic Series

Eric Weisstein's World of Mathematics, Hofstadter's Q-Sequence

Index entries for sequences related to Stern's sequences

Index entries for Hofstadter-type sequences

Mathematica

a[0] = 0; a[1] = 1; a[n_] := If[EvenQ[n], a[n/2], a[(n - 1)/2 - a[(n - 1)/2]] + a[(n - 1)/2 - a[(n + 1)/2]]]; Table[a[n], {n, 0, 100}]

Crossrefs

Cf. A002487, A005185, A287476, A287477.

Sequence in context: A330443 A268479 A035196 * A158020 A051160 A051159

Adjacent sequences: A287472 A287473 A287474 * A287476 A287477 A287478

Keyword

nonn

Author

Ilya Gutkovskiy, May 25 2017

Status

approved