login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A376733
a(1) = 0; for any any n > 1, if A376637(n) starts with a digit 1 then a(n) = 2*a(A376676(n)) otherwise a(n) = 2*a(A376676(n)) + 1.
2
0, 1, 2, 4, 5, 3, 10, 8, 9, 11, 18, 6, 20, 21, 7, 19, 22, 36, 16, 40, 41, 17, 37, 23, 14, 12, 13, 15, 42, 82, 38, 44, 32, 72, 73, 33, 45, 39, 83, 43, 74, 34, 46, 80, 81, 47, 35, 75, 26, 30, 28, 24, 25, 29, 31, 27, 78, 164, 84, 144, 64, 88, 89, 65, 145, 85, 165
OFFSET
1,3
COMMENTS
The binary expansion of a(n) encodes the position of A376637(n) within the binary tree underlying A376676 (see illustration in Links section).
This sequence is a bijection from the positive integers to the nonnegative integers.
FORMULA
A070939(a(n)) = A376698(n) for any n > 0.
EXAMPLE
See illustration in Links section.
PROG
(PARI) \\ See Links section.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Rémy Sigrist, Oct 03 2024
STATUS
approved