InterpolatingPolynomial

InterpolatingPolynomial[{{x1, f1}, {x2, f2}, ...}, x] constructs a polynomial in x passing through the given points.

InterpolatingPolynomial[{f1, f2, ...}, x] uses successive integer x values.

Examples

Through three points:

InterpolatingPolynomial[{{0, 1}, {1, 3}, {2, 7}}, x]
(* 1 + x + x^2 *)

Simplified:

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