Template:Sequence of the Day for July 28

Intended for: July 28, 2012

Timetable

• First draft entered by Alonso del Arte on May 28, 2011 ✓
• Draft reviewed by Alonso del Arte on July 22, 2011 ✓
• Draft to be approved by June 28, 2012

Yesterday's SOTD * Tomorrow's SOTD

The line below marks the end of the <noinclude> ... </noinclude> section.

---

A006127:

2 n + n, n   ≥   0

.

{ 1, 3, 6, 11, 20, 37, 70, 135, 264, 521, 1034, 2059, 4108, 8205, ... }

In The Book of Numbers, John Conway and Richard Guy coyly describe this sequence as “not very different from the powers of 2.”