They're in hexadecimals Soul Blade, if you want to see their normal numbers just look at the script using the debugger.
Plus I think this NPC will make a string list of all onwall tiles:
NPC Code:
if (playerenters) {
setstring onwall.string,;
for (this.i=0;this.i<4080;this.i++) {
board[0]=this.i;
if (onwall(0,0)) setstring onwall.string,#v(this.i);
}
}
It's untested, but if it works you could also check for onwater tiles.