Riffs & Rotes & A061396

[David W. Wilson]

Jon Awbrey wrote:
>
> [stuff omitted] 
> 
> Vladeta Jovovic wrote:
> >
> > Dear Jon Awbrey,
> >
> > Welcome to SeqFan community!
> >
> > I tried  to calculate your seq. A061396 and got:
> >
> > 1, 1, 2, 6, 20, 73, 281, 1124, 4618, 19387, 82765, 358245, 1568458, 6933765, 30907194,
> > 138760603, 626898401, 2847946941, 13001772692, 59618918444 *, 274463781371 *, 1268064807409 *,
> > 5877758070220 *, 27325789128330 *, 127384553264327 *, 595318139942874 *, 2788598203340643,
> > 13090395266913748, 61571972632103632, 290146443773731410, 1369624976703419031
> >
> > My calculation for a(8) gives 4618.
> >
> > Best wishes,
> > Vladeta Jovovic
> 
> ¤~~~~~~~~~¤~~~~~~~~~¤~~~~~~~~~¤~~~~~~~~~¤~~~~~~~~~¤
> 
> David W. Wilson wrote:
> >
> > I computed this sequence from the g.f.  I get
> >
> > 1, 1, 2, 6, 20, 73, 281, 1124, 4618, 19387, 82765, 358245, 1568458, 6933765, 30907194,
> > 138760603, 626898401, 2847946941, 13001772692, 59618918447 *, 274463781383 *, 1268064807513 *,
> > 5877758071073 *, 27325789133590 *, 127384553287387 *, 595318140045752 *
> >
> > [etc]

I did my calculations in Perl, which apparently has a problem with 64-bit
arithmetic.
I redid the calculation in C++, and my results now corroborate Vladeta's.  Use
his
sequence:

1 1 2 6 20 73 281 1124 4618 19387 82765 358245 1568458 6933765 30907194
138760603 626898401 2847946941 13001772692 59618918444 274463781371
1268064807409 5877758070220 27325789128330 127384553264327
595318139942874 2788598203340643 13090395266913748 61571972632103632
290146443773731410 1369624976703419031