Possible reason for exclusion of 8s in A111065

[Robert G. Wilson v]

Excellent point. When I edited the sequence, I just stated that the
title should be "Strobogrammatic numbers (A000787) excluding the
digits 1 and 8." You give a reason for why they were not included.

Bob.

Alonso Del Arte wrote:

> For the recently added A111065, numbers that look the same when
> printed upside down, a note says that for some reason 8s have been
> excluded.
> 
> The reason could be that 8s in most fonts have a slightly bigger
> bottom circle. To some people, this might be a large enough difference
> to realize the number is upside down. Sequences of this sort are very
> dependent on not just a specific character set (the Wikipedia article
> on strobogrammatic numbers notes that these numbers would not be
> strobogrammatic in the Gurmukhi script of India) but on a specific
> font. Thus, 1s have probably been also excluded from A111065 because
> 1s on most Roman script fonts have top serifs.
> 
> Alonso
>