fffg.spad line 593 [edit on github]
This package exports Newton interpolation for the special case where the result is known to be in the original integral domain
newton(l) returns the interpolating polynomial for the values l, where the x-coordinates are assumed to be [1, 2, 3, ..., n] and the coefficients of the interpolating polynomial are known to be in the domain F. I.e., it is a very streamlined version for a special case of interpolation.