Source

phone2word / comparisons.txt

Other services providing this are available online, for example:

phonespell.org
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For 1333133

http://phonespell.org:
1-fed-1-Ed
1-fee-1-Ed

My algo, given a dictionary containing just fee,fed,Ed:
1-Ed-31-Ed
1-fed-1-Ed
1-fee-1-Ed
13-Ed-1-Ed

In general my algo seems to be produce far more results.