Copyright only protects "unnecessary", i.e. creative work. If there's only one way to do something (eg. maths), it can't be protected by copyright. If copyright

Copyright only protects "unnecessary", i.e. creative work. If there's only one way to do something (eg. maths), it can't be protected by copyright. If copyright is an obstacle to somebody creating something, they always have the freedom to create something different and just as good instead.