An expanded part of https://gist.github.com/tjluoma/a4a3bc2b61278243b0e5

sundays-revised.sh

while [ "$YEAR" -le "${STOP}" ]
do
	# calculate and print the date
	# Note that you can control the format of the date here too
	DATE=`gdate --date "+${COUNT} day" '+%B %d, %Y'`

cat <<EOINPUT
* ${DATE}
	* []()
	*
EOINPUT

	# increment the counter
	COUNT=`expr ${COUNT} + 7`

	# check the resulting year
	YEAR=`gdate --date "+${COUNT} day" '+%Y'`

done