[seqfan] Re: Re Mystery of A049476

[Peter Munn]

On Mon, August 2, 2021 4:56 pm, Neil Sloane wrote:
[...]
> Fred Roush did have some suggestions that might help clear up the
> mystery.  Here is what he said:
>
> (i)  A088643 seems pretty clear
[...]
> and in a follow-up he said:
>
> (ii)  Maybe what we were looking for is in each row the first interval of
> numbers n, n-1, ..., n-k+1  which is permuted onto itself by the
> row considered as a permutation.  This seems to work for 1, 2,  5, 13, 14.
>  This set of numbers has then a gap down to the next
> such set of numbers.

To get this to work for the next two terms of A049476 (26 and 61), I have
to modify the rule Fred Roush suggests above.

I think a further condition might be that n-k is left unchanged by row n
considered as a permutation, so that the last n-k terms of row n are a
copy of row n-k.

Best regards,

Peter