The Sun is very much a main sequence star, in the G-type category (G2V to be precise). It’s been fusing hydrogen for 4.6 ...

leading to a state of equilibrium between gravitational collapse and the energy released during fusion Key fact In a main sequence star, hydrogen nuclei fuse together to form helium nuclei.

116, No. 820 (June 2004), pp. 506-515 (10 pages) ABSTRACT We explore the binary fraction of subdwarf B (sdB) stars by using the Two Micron All Sky Survey (2MASS) to search for main‐sequence companions ...