Template:Sequence of the Day for September 20

Intended for: September 20, 2011

Timetable

• First draft entered by Alonso del Arte on September 11, 2011 ✓
• Draft reviewed by Daniel Forgues on September 19, 2018 ✓
• Draft to be approved by August 20, 2011

Yesterday's SOTD * Tomorrow's SOTD

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A000975:

a (0) = 0; a (2 n) = 2  a (2 n  −  1), a (2 n + 1) = 2  a (2 n) + 1, n   ≥   1.

{ 0, 1, 2, 5, 10, 21, 42, 85, 170, 341, ... }

These are also numbers with no consecutive equal bits in their binary representations (cf. A056830)

{0, 1, 10, 101, 1010, 10101, 101010, 1010101, 10101010, 101010101, 1010101010, ...}