+# cut -b 2-
+# convert_sn() {
+# local sn a b c d
+# sn="$1"
+# if [ -z "$sn" ] ; then read sn; fi
+# a="${sn%??????????????????????????}"; sn="${sn#??????}"
+# b="${sn%????????????????????}"; sn="${sn#??????}"
+# c="${sn%??????????????}"; sn="${sn#??????}"
+# d="$sn"
+#
+# if [ "${c#0000}" = "$c" ]; then
+# echo >&2 "sn has unexpected value ($1: $a - $b - $c - $d)"
+# return 1
+# fi
+#
+# echo "36${a}000${b}${c#0000}${d}"
+# return 0
+# }
+
+