Games played by Yuuki Oosumi (Moriyama, Japan) in this fuseki

2
1
3
54
4bw
+2 
=1 
- 1
?  

1Nakamura Shigeru - Oosumi Yuuki
2Oosumi Yuuki - Nagao Noriaki
3Oosumi Yuuki - Kamiya Shunsuke
4Oosumi Yuuki - Kashihara Akihiko