Template:Sequence of the Day for November 26

Intended for: November 26, 2011

Timetable

• First draft to be entered by August 26, 2011
• Draft to be reviewed by September 26, 2011
• Draft to be approved by October 26, 2011

Thanksgiving will fall on November 26 in the years 2015 and 2020.

Yesterday's SOTD * Tomorrow's SOTD

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

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A000055: Number of trees with

n, n   ≥   0,

unlabeled nodes.

{ 1, 1, 1, 1, 2, 3, 6, 11, 23, 47, 106, 235, ... }

Trees with

n

unlabeled nodes

n	Trees
0	Null tree
1	●
2	●—●
3	●—●—●
4	● / ●—●—●—● ●—● \ ●
5	● ● / | ●—●—●—●—● ●—●—● ●—●—● \ | ● ●

This is the sequence for the example search on the front page of the OEIS. This Thanksgiving we are thankful for, among other things, the OEIS, which is an invaluable resource in many mathematical and scientific endeavors.

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