I need to use the contents of an array function as the elements of a
concatenation.
In it's simplest form, concatenate(a1,a2,a3) works, but concatenate(a1:a3)
doesn't.

My (attempted) formula was:
=CONCATENATE(IF(H6:H179*E6:E1790,D6:D179,"")), entered as an array.
It passes the results of the "" IF" as value1;value2;value3 etc, and only
the first value comes through into the concatenation.
Alternatives involving 174 separate "if"s, just aren't going to work!