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davar55 2010-02-16 20:45

Help Find a Sequence?
 
I'm trying to find a certain sequence, so far without success.
I don't want to paste pingpong balls together, especially since
this obvious sequence must have already been computed or counted.
Help, please?

The sequence begins with 1,13,?,?,?
and gives the number of identical spheres in a most
tight packing around the previous smaller packing,
starting with one sphere.

Mini-Geek 2010-02-16 21:07

[url]http://www.research.att.com/~njas/sequences/?q=1%2C13+sphere&sort=0&fmt=0&language=english&go=Search[/url]

davar55 2010-02-19 16:54

Thank you. The second sequence you found, A005902, that
begins with [B]1, 13[/B], 55, 147, 309, 561, 923, 1415, is what I was
looking for. I'm surprised I missed it when I searched, but I had
expected the third term to be smaller.


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