Harmonic Function

[MohamedE]

This formula doesn't work:

Sum[1/i, {i,1,n}]

See: http://www.wolframalpha.com/input/?i=Sum%5B1%2Fi%2C+%7Bi%2C1%2Cn%7D%5D

[Axel Kramer]

Now returns

>>> Sum[1/i, {i,1,n}]
HarmonicNumber(n)

http://symjaweb.appspot.com/?ci=ta:Input:t:Sum%5B1%2Fi%2C%20%7Bi%2C1%2Cn%7D%5D

See: Wikipedia Harmonic Number