Syver Larsen was from where? and went where?

I'm a bit embarrassed to ask for your help but I've spent considerable time with this particular problem and don't seem to be making much headway by myself. I'll lay out the vital documents I've already uncovered and give you links while explaining the problems I'm having. I'd appreciate your advice and suggestions. My hope is to someday be find earlier documentation for Syver Larsen. 1. Hans Syversen was born out of wedlock 17 Dec 1819 in Gran, Oppland, Norway to bachelor Syver Larsen and maiden 21 yr old Anne Erichsdatter. That record says Syver Larsen comes from Land Prestegjeld, Oppland. I am unable to decipher all of what is written in the far right hand column but that seems to be repeated for other illegimate births also. Gran prestekontor, Ministerialbok nr. 9, 1815-1824, s. 98-99; record #11 at the bottom of the left hand page; https://www.digitalarkivet.no/kb20070603850442 Gran prestekontor, Klokkerbok nr. 1, 1815-1824, s. 98-99; record #11 at the bottom of the left hand page; https://www.digitalarkivet.no/kb20070603850140 I'm NOT concerned with Anne Erichsdatter - I've been able to track her life and her ancestors to my current satisfaction. I'm also NOT concerned with the witnesses/sponsors to the child's baptism. Syver Larsen is of some great concern. I have been unable to locate Syver/Siver Larsen/Larssen in Land Prestegjeld or later in Hadeland - at this current time I'm exploring other nearby districts in southern Oppland... There is no notation of Syver being a soldier which had come to mind but I've had to set aside. 2. Hans Syversen is confirmed 28 Sept 1834 in Gran, Oppland. Gran prestekontor, Ministerialbok nr. 10, 1824-1842, s. 534-535; record #36; https://www.digitalarkivet.no/kb20070603860278 This record appears to list his father as Syver Hansen?? (Time for me to panic? No, but it was discouraging to first find.) 3. Hans Syversen marries Karen Amundsdatter in Jevnaker, Oppland 30 Dec 1849. They had a daughter out of wedlock 15 Feb 1848 in Jevnaker and that daughter died 13 August 1850 on Hovelsrudeie in Jevnaker. The marriage record lists his father again as Syver Larsen. Karen Amundsdtr dies 5 Nov 1852 in Jevnaker. Jevnaker prestekontor, Ministerialbok nr. 6, 1837-1857, s. 196; record #34; https://www.digitalarkivet.no/kb20070205640028 4. Hans Syversen marries Anne Halvorsdtr 24 Jan 1854 in Jevnaker, Oppland. The record lists his father again as Syver Larsen. Jevnaker prestekontor, Ministerialbok nr. 6, 1837-1857, s. 209; record #14; https://www.digitalarkivet.no/kb20070205640040 Hans and Anne have 6 children together in Jevnaker. Halvor 26 Aug 1854; Ole Christian 5 Aug 1857; Rolf 7 Dec 1860; Anne Sofie 28 Apr 1864; Karen Oline 28 Sept 1867; and a short lived unnamed male child born 21 Dec 1871. None of those children's records give any indication of Hans father's name or origin. 5. Hans Syversen dies 30 Jan 1873 on Vestern in Jevnaker, Oppland. Jevnaker prestekontor, Ministerialbok nr. 7, 1858-1876, s. 260; record #8; https://www.digitalarkivet.no/kb20070205640433 The child Rolf Hansen was my great-grandfather, he lived a long life in the US, having many children. His mother and one of sisters lived in the same midwestern US county and I know everything important that happened to them. But Rolf's paternal grandfather, Syver Larsen, remains my haunting mystery. I'm very willing to work and try my darndest but I'm short on new ideas.