The two Danish Haralds on that list are not included in the official list of kings. Admittedly, Harald Blåtann was formally the King of Norway from 970 onwards, but Håkon, the Earl (Jarl) of Lade, ruled Norway on his behalf, and then on behalf of Harald's son Svein, from 970 to 995 - and it is he who is included in the official list of rulers and regents of Norway. (But he was not a king, so he is not assigned a regnal number.)

I assume that Harald Sveinsson is the same as Harold Harefoot (Harold I) of England? He is not included in the list of Norwegian rulers either - usually, Eirik and Svein, the sons of the aforementioned Jarl Håkon of Lade, are listed as rulers of Norway, on behalf of the Danish king, until Olav II (St. Olav) claimed the throne in 1015 or 1016.