a factor $(4\pi)^2$. It can be further recast in terms of the $a$-anomaly introduced in (\[eq:acdef\]) by noting that the Gauss-Bonnet density is $E_4 = 24/\ell^4_A$. We have included the $a$-anomaly computed this way in table \[table:Kmassless\]. These values agree perfectly with the results from the local expansion in curvature summarized in table \[table:centralcharges\].

There is a caveat to this agreement. As we have stressed, our computation (which in fact closely follows Camporesi and Higuchi [@Camporesi:1993mz]) determines the $a$-anomaly unambiguously for all spin. In contrast, many researchers compute both $c$ and $a$ for low spin but results for $s={3\over 2}, 2$ (and above) are not widely quoted and there is no obvious consensus on their values. This situation is tied with the background dependence of the linearized equations of motion for such fields. The most secure data points are for $c-a$ which is defined in Ricci flat backgrounds and $a$ which, as we have stressed, is unambiguous in maximally symmetric spacetimes. For $s={3\over 2}, 2$ the values of $a, c$ given in table \[table:centralcharges\] were obtained by combining the results for $a$ given in table \[table:Kmassless\] with the standard values of $c-a$.

Extended SUSY
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The $t$-poles in the heat 