Banjo Bmaj7 chord (Open G)B major seventh on the 5-string banjo: 1 3 0 4, and 5 more shapes

Frets, string 4 to string 1: 1 3 0 4 (open position)

1. String 4 (D): 1st fret, index finger, D♯
2. String 3 (G): 3rd fret, ring finger, A♯
3. String 2 (B): open, B
4. String 1 (D): 4th fret, little finger, F♯
5. String 5, the short g: open, G, not in the chord

Sounds: D♯ A♯ B F♯  ·  Bmaj7 is B, D♯, F♯, A♯ (1 · 3 · 5 · 7)

The 5th string: the short g rubs against the F♯ in this shape, a semitone away: some players let it ring, some skip it.

Open G tuning: gDGBD, the short 5th string first, then strings 4 to 1.