Q (27 characters)

while[72<>sum a:18?3 4 5];a

Sample output

4 4 3 3 4 5 4 3 4 5 5 3 5 5 5 4 3 3

Q (25 characters)

Original (27)

while[72<>sum a:18?3 4 5];a

Sample output

4 4 3 3 4 5 4 3 4 5 5 3 5 5 5 4 3 3

Slightly shorter (25)

{72<>sum x}{x:18?3 4 5}/0