Counting Distinct Diagrams in Scalar Field Theory

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I was just trying to think of a simple relation to find the number of distinct diagrams to a given order within a theory (specifically I am thinking of a \phi^{4} scalar theory). I am reading Tony Zee's book and am working through his "baby problem" where he expands the integral:

\int_{-\inf}^{\inf} dq e^{-\frac{1}{2}m^{2}q^{2}+Jq-\frac{\lambda}{4!}q^{4}

in both in powers of \lambda and J so that we can pick out diagrams to a specific order in both.

So is there a way to find the total number of distinct diagrams to order (\lambda^{n},J^{m})?

Thanks in Advanced :smile:
 
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to be honest, i have no idea.
 
From personal experience, you just keep working these out by hand until you see a pattern. Or you get to a point where you give up. If there is a better way, I have not found it.
 
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