Harmonic numbers on the HP 50g

[Peter Murphy]

I recently discovered that the HP 50g function Psi (in MTH NXT SPECIAL) delivers the nth harmonic number:

Hn = Psi(n + 1) – Psi(1)

[and that, by the way, –Psi(1) = 0.577215664902, the Euler constant].

This observation, together with the numerical SOLVE command, allows quick disposal of (say) the problem of finding the smallest integer k for which Hk > 7.6, and it might more generally be useful in mathematics teaching.