[seqfan] Underlined sequences.
franktaw at netscape.net
franktaw at netscape.net
Fri May 6 09:20:11 CEST 2011
In https://oeis.org/draft/A190013, Jonathon Vos Post has submitted a
sequence from a paper. The (finite) sequence in the paper looks like:
0, 1_, 3, 0_, 2, 4_, 1, 3_, 0, 2_, 4, 1_, 2, 3_, 4, 0_, 1, 2_, 3, 4_,
0_, 0, 2, 2_, 3_, 3, 4, 4_, 1_, 1
where the trailing underscore here represents an underlined number in
the paper. The question is how to represent this sequence in the
database.
Note first that this is described as a sequence over a 10-element
alphabet, so the actual values are not really significant. My
suggestion was to add 5 to the underlined values, giving
0, 6, 3, 5, 2, 9, 1, 8, 0, 7, 4, 6, 2, 8, 4, 5, 1, 7, 3, 9, 5, 0, 2, 7,
8, 3, 4, 9, 6, 1
If the values were strictly positive, I would favor making the
underlined values negative, but that won't work here. One could take n_
to -1-n, but that seems even more artificial than the +5 suggestion.
Likewise for n -> 2n, n_ -> 2n+1.
The main problem with my solution is that someone seeing the sequence
in the paper and looking for it in the database is probably not going
to find it.
Maybe we need two sequences, one with the original values ignoring
underlines, and the other with the +5.
Any suggestions? opinions?
Franklin T. Adams-Watters
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