Try this (in an EG code node -- NOT as a stored process). Probably WEEKDATX is the format you want. The documentation on SAS formats is quite extensive and and overview and list of formats can be found under the topic:
Dates, Times, and Intervals --> About SAS Date, Time, and Datetime Values
in the online documentation.
input name $ bday1 : mmddyy10.;
bday2 = bday1;
bday3 = bday1;
bday4 = bday1;
bday5 = bday1;