Wolstenholme number
A Wolstenholme number is a number that is the numerator of the generalized harmonic number Hn,2.
The first such numbers are 1, 5, 49, 205, 5269, 5369, 266681, 1077749, … (sequence in the OEIS).
These numbers are named after Joseph Wolstenholme, who proved Wolstenholme's theorem on modular relations of the generalized harmonic numbers.
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