[Haskell-beginners] Finding Keith Numbers with Haskell

[Rein Henrichs]

On Tue, Nov 11, 2014 at 5:26 AM, Jack Mott <jack.mott at gmail.com> wrote:

> I did try this approach as well, reversing the digits and adding elements
> to the head, however having to use take and letting the list build  up
> larger seems to result in slightly worse performance overall.
>

The list doesn't build up. The specification for Keith Numbers requires
that we only sum the previous n numbers, where n is the length of the
decimal encoding of the given number, so we always truncate using take
before the recursive call.
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