Restrict users do not apply for Absence Mid of week

Summary

There is a requirement to restrict users in case of Maternity Absence applying do not applying in the mid of the week. It should be Monday to Friday.

Content

Any idea to restrict user do not apply absence in the Mid of the week like if I am applying from Wednesday system will error. It can be achieved through Fast Formula ( Absence entry validation).

Can anybody assist to write this condition?

Thanks.