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Many of the source files refer to a non-existent LICENSE file.  The license 
listed for the project is the New BSD license, so this file should probably be 
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In the original BSD license, the occurrence of "copyright holder" in the 3rd 
clause read "ORGANIZATION", placeholder for "University of California". In the 
original BSD license, both occurrences of the phrase "COPYRIGHT HOLDERS AND 
CONTRIBUTORS" in the disclaimer read "REGENTS AND CONTRIBUTORS".

Here is the license template:

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Huge speedup & simplification of the Round function.

The interface and naming doesn't match the rest of go-fn, but this otherwise 
adds working versions of the upper incomplete gamma function, the inverse of 
the upper incomplete gamma function, the exponential integral E1 and the family 
En. There are certainly several optimizations still possible/needed - large 
alpha, for instance, is not handled well. These have also not been thoroughly 
tested, either, but are numerically sound in the regions I have tried them 
(negative and positive alpha in the region -3, 3, large and small x).

Fixed bug in HarmonicMean ( see http://en.wikipedia.org/wiki/Harmonic_mean ). 
Replaced "math.Log( 1.0 +" in line 109 with math.Log1p for increased numerical 
accuracy.

What steps will reproduce the problem?
Run Choose(3, 2)

What is the expected output? What do you see instead?
Expected: (3 choose 2) = 3
Actual: 6

Please provide any additional information below.
This bug can be solved by changing line #152 in the choose.go file from:
    return PartialFactInt(n, smaller) / FactInt(smaller)
to:
    return PartialFactInt(n, smaller) / FactInt(n-smaller)

What steps will reproduce the problem?
go test (with choose_test.go): first two cases