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Finiteness of UpWords given finite alphabet #4533

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Hopefully I found the right place to put rabss3d after promotion.

paysd.1 $e |- ( ph -> A e. Fin ) $.
paysd.2 $e |- ( ph -> B : A --> RR ) $.
paysd.3 $e |- ( ph -> sum_ k e. A ( B ` k ) = 0 ) $.
paysd.4 $e |- ( ph -> C = (/) ) $.
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I assume this is the initial step of a proof by induction?

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That's a comment with some proof... I'm actually not sure if I want to prove the fact that |A| transfers are sufficient by induction or by explicit construction of C.

tworepnotupword.1 $e |- A e. _V $.
$( Word of two matching characters is never an increasing sequence.
(Contributed by Ender Ting, 22-Nov-2024.) $)
tworepnotupword $p |- -. ( <" A "> ++ <" A "> ) e. UpWord S $=
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Why not -. <" A A "> e. UpWord S ? Then label could be s2repnupword.

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There was such a word constructor? 😮


${
$d S a $. $d T a $.
$( There is a finite number of strictly increasing sequences over finite
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"strictly increasing sequences of fixed length"

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Ah yes, I see how this can become misleading (given that total number of strictly increasing sequences will be finite as well).

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