curated data - Is it possible to invoke the OEIS from Mathematica?

I had always wondered if there might be a way to write a function, which I'll call OEISData[], that more or less works as a curated data function for The On-Line Encyclopedia of Integer Sequences.

I would imagine that the usage might be a little something like this:

OEISData["A004001"][9]
5

OEISData["A003418"][Range[8, 15]]
840, 2520, 2520, 27720, 27720, 360360, 360360, 360360

OEISData["A005849", "Keywords"]

{"hard", "nonn", "nice", "more"}

An API or something to retrieve data from the OEIS site might be needed for an implementation of this function. Is a function like this possible, with what Mathematica is currently capable of?

Answer

There is a Mathematica package exactly for this at the OEIS wiki.

Somewhat related: there's also a package for formatting data into the OEIS format.

WolframAlpha also has some of this information, though I'm not sure how to get the $n^{\mathrm{th}}$ term of the sequence.

In[1] := WolframAlpha["A004001", {{"TermsPod:IntegerSequence", 1}, "ComputableData"}]

Out[1] = {1, 1, 2, 2, 3, 4, 4, 4, 5, 6, 7, 7, 8, 8, 8, 8, 9, 10, 11,

          12, 12, 13, 14, 14, 15}

Or:

In[1] := WolframAlpha["A018900", {{"Continuation", 1}, "ComputableData"}]

Out[1] = {3, 5, 6, 9, 10, 12, 17, 18, 20, 24, 33, 34, 36, 40, 48, 65, 66, 68, 72}