don't try to find blocks with heights less than zero

routes/baseActionsRouter.js

@@ -196,13 +196,17 @@ router.get("/blocks", function(req, res) {
 		var blockHeights = [];
 		if (sort == "desc") {
 			for (var i = (getblockchaininfo.blocks - offset); i > (getblockchaininfo.blocks - offset - limit); i--) {
+				if (i >= 0) {
 					blockHeights.push(i);
 				}
+			}
 		} else {
 			for (var i = offset; i < (offset + limit); i++) {
+				if (i >= 0) {
 					blockHeights.push(i);
 				}
 			}
+		}
 		
 		coreApi.getBlocksByHeight(blockHeights).then(function(blocks) {
 			res.locals.blocks = blocks;