= Three-dimensional quartic Yukawa power-counting identity
{title2=$\omega=3-b/2-f-n_4$}
For a connected amputated <Feynman diagram> with the <quartic Yukawa interaction in three spacetime dimensions>, scalar quartic and scalar sextic vertices, $b$ external bosonic legs, $f$ external fermionic legs and $n_4$ scalar quartic vertices, the <superficial degree of divergence> is the displayed expression. Indeed $\omega=3L-2I_b-I_f$, $2I_b+b=2n_Y+4n_4+6n_6$, $2I_f+f=2n_Y$ and $L=I_b+I_f-n_Y-n_4-n_6+1$. Substitution eliminates the counts of the two marginal vertices. The bound concerns overall <ultraviolet divergence>, before numerator cancellations and subtraction of <ultraviolet subdivergences>.
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