FindSequenceFunction

FindSequenceFunction[{a1,a2,a3,…}] attempts to find a simple function that yields the sequence an when given successive integer arguments.

FindSequenceFunction[{{n1,a1},{n2,a2},…}] attempts to find a simple function that yields ai when given argument ni.

FindSequenceFunction[<|n1->a1,n2->a2,…|>] gives a function that yields ai when given argument ni.

FindSequenceFunction[{n1->a1,n2->a2,…}] gives a function that yields ai when given argument ni.

FindSequenceFunction[list,n] gives the function applied to n.

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