~$ echo $(printf '{1,2}%.0s' $(seq 4))
{1,2}{1,2}{1,2}{1,2}
~$ echo $(printf '{1,2}%.0s' $(seq 3))
{1,2}{1,2}{1,2}
~$ echo $(printf '{1,2}%.0s' $(seq 10))
{1,2}{1,2}{1,2}{1,2}{1,2}{1,2}{1,2}{1,2}{1,2}{1,2}
~$ eval echo $(printf '{1,2}%.0s' $(seq 3))
111 112 121 122 211 212 221 222
~$