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# gorensteinDouble -- attempts to produce a Gorenstein double structure J subset I

- Usage:
    `gorensteinDouble I`
- Inputs:
  - I, an ideal,
- Outputs:
  - J, an ideal,

## Description

Let S = ring I, and that I is an ideal of codimension c. Let F be the S-free resolution of S/I. Assuming that S is a polynomial ring and S/I is Cohen-Macaulay, the canonical module of S/I is omega = coker transpose F.dd_c. The script returns the ideal J that is the kernel of the first element of Hom(I, omega). In case I is the ideal of a scroll there is a unique element of minimal degree, and it represents a surjection, so S/J is Gorenstein.

## Ways to use gorensteinDouble:

- `gorensteinDouble(Ideal)`

## For the programmer

The object gorensteinDouble is a method function.

The source of this document is in /build/macaulay2-88fgJW/macaulay2-1.25.11+ds/M2/Macaulay2/packages/K3Carpets.m2:1674:0.