Equivariant vertex is a very important special function allowing computations of Donaldson-Thomas/Pandharipande-Thomas partition functions for toric varieties. Such partition functions turn out to be rational in the boxcounting parameter, and it has an interpretation in M-theory. I will prove the conjecture from the paper of N.Nekrasov and A.Okounkov relating double curve counts in DT/PT theory on the total sum of 2 line bundles over $\mathbb{P}^1$ with M2-brane counts on a certain Calabi-Yau 5-fold. For that I will consider relative theories with boundary conditions on divisors.