Big numbers, programming contest

Ed Pegg Jr edp at
Mon Jul 4 19:14:25 CEST 2005

For recently, I ran a puzzle based on
sequence A023199 -- a(n) = least k with sigma(k) >= nk

The numbers there get large quickly, unless they are represented
differently.  Then, they are quite managable.  I'm not sure what
the ninth term is.  The sequence 3 5 11 17 29 53 89 157 XX 487
seems interesting as well.

{3!, 5!, 11#3!2, 17#5!2, 29#7!4, 53#7!12, 89#11!2,
157#17#8!6, ???, 487#*29#*10!/2}

Perhaps the sequence, in this form, could be extended in the comments.

NJA and the Seq Fan list helped with defining some interesting
problem sets.  Now, the Al Zimmermann programming contests have
returned.  Not as sequency as
the upcoming challenges.  Feel free to suggest any new challenges
to the discussion board at the site.

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