I have a math degree and know if many cases even nowadays were "amateurs" find good solutions.

Don't wanna go to much into details but in order to calculate the likelihood of a solution (which is not alien to number theory). You'd need to calculate the density of possible products of single digits numbers in a number range.(easily done with the sieve approach)

Since the number of 11 step solutions becomes infinite by just adding more 1s it's probably not that unlikely to find a solution with several hundreds or thousands digits.*

Otherwise you'd need to prove why it's impossible. ( Which could be done by showing that the density becomes 0)

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery FootballPerl is like chess, only without the dice

update
*) or at least prove it's existence.

In reply to Re^5: Multiplication digit persistence by LanX
in thread Multiplication digit persistence by tobyink

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