[seqfan] Re: How many numbers have n letters?

[Hans Havermann]

I remember working on one of these: https://oeis.org/A121064

> On Apr 22, 2023, at 11:24 PM, Neil Sloane <njasloane at gmail.com> wrote:
> 
>> The terms a(1) though a(10) are: 0, 0, 4, 3, 6, 6, 3, 13, 22, 35, and (my) definition is that a(n) is the number of [nonnegative / positive] numbers whose standard name in [British / American] English has n letters, or -1 if there are infinitely many numbers with n letters. So there are really four sequences. The only difference between nonnegative and positive is at n=4, where we get 3 for positive numbers (four, five, nine) or 4 for nonnegative numbers (include zero). Up though n=10 there is no difference between British and American English, according to GCHQ.