[seqfan] Re: Offsets for Recurrence Sequences
N. J. A. Sloane
njas at research.att.com
Thu Apr 23 18:10:28 CEST 2009
Creighton, the OEIS policy is to start a sequence at the earliest
reasonable point, but no earlier
The Fibs could have begun 1 1 2 3 ... or 1 2 3 5 8 ..., but the
universally accepted version starts 0 1 1 2 3 5 8 ... and there are very
good reasons for this
(having to do with theorems that say that F(n) has
some property iff n has some other property
The situation with regard to the Lucas numbers is quite different.
There are good reasons for having them begin 1 3 4 7 ...
and also for 2 1 3 4 7 ... . Especially because the OEIS
is arranged lecicographically acc. to the first term > 1 in magnitude.
so whereas all the versions of the Fibs would appear in the same place in
the ordering, the Lucas numbers could appear in two different places.
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