rwg>Here is an almost correct technique for printing number triangles, of which Julian must repeatedly remind me: pt[n_Integer, from_Integer: 0] := TableForm[Table[If[EvenQ[i + j], "", Binomial[-1 + i, -Floor[n/4] + (1 + i + j)/2] /. 0 -> ""], {i, from, n}, {j, -Ceiling[3*n/4], n + 1}]] [...] Duh, for actual symmetrical triangles, In[516]:= Column[Table[Row[Table[Binomial[n,k],{k,0,n}]," "],{n,0,5}],Center] Out[516]= 1 1 1 1 2 1 1 3 3 1 1 4 6 4 1 1 5 10 10 5 1 --rwg I somehow missed the distressing answer that Maple has been bodysnatched by the same brain virus (or is it Toxoplasma?) that's corrupted Mma: http://isc.carma.newcastle.edu.au/standardCalc accepts Maple input. Standard lookup results for *Pi^binomial(-2,-6)* Best guess: Pi^(5) Both leading CASs! Maybe they think it's just a matter of personal preference, like whether toilet paper spools off the front or the back?