You can
put this solution on YOUR website!
If we start with the complete alphabet:
ABCDEFGHIJKLMNOPQRSTUVWXYZ
and choose 19 of the letters to remove, for instance like this:
A---E--H-JK------R------Y-,
that will leave the alphabetically ordered 7-letter "word" AEHJKRY.
So from the 26 letters we want to choose 19 to remove.
Answer: C(26,19) = 657800
Edwin