auto tellsimpafter repetition?



On Nov. 20, 2010, Richard Fateman wrote
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You can try tellsimp.   or apply rules using apply1

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Since so far,  ev( comm(...), infeval ) is doing the
 job, I will keep on the tellsimpafter track for now.

But in a fresh Maxima start, why doesn't the following
pattern matching work?

(%i1) matchdeclare(aa,atom,bb,atom,cc,atom)$
(%i2) matchdeclare(nn,integerp,mm,integerp,pp,integerp)$
(%i3) tellsimpafter(
         comm (aa^^nn   .  bb^mm,  cc),
         aa . comm(aa^^(nn-1) . bb^mm,cc) +
            comm(aa^nn . bb^(mm-1),cc) . bb)$
(%i4) comm(a^^2 . b^^2,c);
(%o4) comm(a^^2 . b^^2,c)
(%i5) comm(a^^3 . b^^2,c);
(%o5) comm(a^^3 . b^^2,c)

Perhaps the expression  

   aa^^nn   .  bb^mm

is held internally in a different form?

Ted