[seqfan] Re: guessing doubling formulas for sequences

[Georgi Guninski]

On Tue, Mar 10, 2009 at 08:05:30AM -0700, Joshua Zucker wrote:
> In some sequences, a_{2n} comes easily from a_{n-1} and a_n, so
> perhaps you should include a term or two before a_n also.  Though
> maybe you handle that difference just by changing the offset of the
> sequence by 1?
>

yes.

i should have written a_{n-k},..,a_n,..a_{n+k}