Problem Description

PR #39480 enhanced the __getitem__ method of multivariable power series, so that individual coefficients of a power series f can be accessed via the syntax f[n1, n2, ..., nk]. (This facility was already available for multivariate polynomials.) However, the discussion on that PR pointed out that it would be helpful for polynomials, power series, and lazy power series to have a uniform interface,

Proposed Solution

LazyPowerSeries should be enhanced to have the same easy access to coefficients via f[n1, n2, ..., nk]. (A similar enhancement was also suggested for other related classes, such as LazySymmetricFunctions and LazyCompletionGradedAlgebra.)

It would also be good to make f[n] return the homogeneous component of degree n (as is the case for multivariate polynomials and multivariate power series).

Alternatives Considered

None.

Additional Information

No response

Is there an existing issue for this?

• I have searched the existing issues for a bug report that matches the one I want to file, without success.