[seqfan] Re: An interesting sequence

[Fred Lunnon]

Ouch --- thanks.
Now that blunder is fixed, my brute-force Magma lash-up finds

    x = 5  for  n  in  {5, 19, 24, 32, 33, 44, 48, 76} ;

    76 = ( 3^2 + 5^2 + 9^2 + 11^2 + 12^2 )/5 .

No further zeros up to next standout case at  n = 96 .

WFL


On Sun, Apr 16, 2023 at 11:23 AM <jens at voss-ahrensburg.de> wrote:

>
> a(11) = 5 since 11 = (25 + 16 + 9 + 4 + 1) / 5.
>
> Am 2023-04-16 12:07, schrieb Fred Lunnon:
> > << only a(2), a(3), a(6), a(8), a(12) are 0 >>
> >
> > What about  n = 11  ?!     WFL
> >
> >
> >
> > On Sun, Apr 16, 2023 at 6:07 AM Yifan Xie <xieyifan4013 at 163.com> wrote:
> >
> >> Hi,
> >> a(n) is the smallest positive integer x such that n can be expressed
> >> as
> >> the arithmetic mean of x distinct nonzero squares, or 0 if x does not
> >> exist. Based on my calculation of a(1) to a(76) by hand, only a(2),
> >> a(3),
> >> a(6), a(8), a(12) are 0 and no terms are larger than 5.
> >> Please consider this sequence, and if possible, provide a program for
> >> me.
> >>
> >> Best regards,
> >> Yifan Xie (xieyifan4013 at 163.com)
>
>
> --
> Seqfan Mailing list - http://list.seqfan.eu/
>