Distributions of detectable galactic number counts by SDSS DR7 within a radius of 0.5 Mpc (a), 1.0 Mpc (b), and 3.0 Mpc (c) and a redshift gap of z ± 0.04(1 + z) for our LSB galactic sample (blue), compared with all the α.40 galaxies (black). We normalize both peaks of blue and black to 1.0, so they can be easily compared. The gray dashed line represents N_gal = 8, which is the lower limit of the neighboring galactic counts of a galactic candidate in a cluster, and the gray solid line represents N_gal = 16, which is the peak of the neighboring galactic count distribution for galactic candidates in clusters. We also show the distribution of the detectable galactic number count with a radius of 1.0 Mpc against the H I mass for this LSB galactic sample in panel (d), in which the gray broken line represents the trend between the mean H I mass and the mean number count of neighboring galaxies in nine HI mass bins with a bin size of 0.5 dex in log M(H I)/M⊙.