Two sequences with sod: more terms?

Richard Guy rkg at
Sun Feb 10 22:36:11 CET 2008

Glad that someone besides myself was bewildered
by `sod'.   Can we find something that's more
self-explicative and less offensive?  `digit-sum'
or  `digitsum'  may not be too cumbersome?   R.

On Sun, 10 Feb 2008, hv at wrote:

> zak seidov <zakseidov at> wrote:
> :%N A000001 Numbers n such that sod(n^2}=10. Multiples
> :of 10 are omitted.
> [...]
> :%N A000001 Numbers n such that n and n^2 have the same
> :sod=10. Multiples of 10 are omitted.
> I hope you'll add an explanation of "sod" as well - my initial guess
> was "sum of divisors", but that clearly isn't what is intended here.
> None of mathworld, planetmath or wikipedia illuminate.
> It isn't until I search on OEIS itself that I find "sum of digits".
> For the few extra letters required, I'd suggest spelling it out.
> I found that OEIS has 45 matches for "sod", of which some have a comment
> explaining the term, but not all. I didn't check whether they all
> use it to mean the same thing.
> Note also that in British and Australian English "sod" has a pejorative
> sense (though far more mildly so than its origins might suggest). I would
> not for a moment suggest replacing it for that reason, but others might.
> Hugo

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