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adrian_byesterday at 9:28 AM1 replyview on HN

Hypergeometric functions are functions with 4 parameters.

When you have a function with many parameters it becomes rather trivial to express simpler functions with it.

You could find a lot of functions with 4 parameters that can express all elementary functions.

Finding a binary operation that can do this, like in TFA, is far more difficult, which is why it has not been done before.

A function with 4 parameters can actually express not only any elementary function, but an infinity of functions with 3 parameters, e.g. by using the 4th parameter to encode an identifier for the function that must be computed.


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thaumasiotesyesterday at 10:05 AM

> Hypergeometric functions are functions with 4 parameters.

Granted, but the claim in the abstract says:

>> computing elementary functions such as sin, cos, sqrt, and log has always required multiple distinct operations

And I don't see how this is true as to hypergeometric functions in a way that isn't shared by the approach in the paper.

> Finding a binary operation that can do this, like in TFA, is far more difficult, which is why it has not been done before.

> A function with 4 parameters can actually express not only any elementary function, but an infinity of functions with 3 parameters, e.g. by using the 4th parameter to encode an identifier for the function that must be computed.

These statements seem to be in direct conflict with each other; you can use the second parameter of a binary function to identify a unary function just as you can use the fourth parameter of a quaternary function to identify a trinary one.

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