Generate a Gallery of Indefinite Sums
Generate a variety of indefinite sums.
 In[1]:= ```problems = {HoldForm[ \!\(\*UnderscriptBox["\[Sum]", "k"]\)(k^2 + 5 k + 7)], HoldForm[ \!\(\*UnderscriptBox["\[Sum]", "k"]\)2^k k^5], HoldForm[ \!\(\*UnderscriptBox["\[Sum]", "k"]\)k/((k + 1) (k + 3))], HoldForm[ \!\(\*UnderscriptBox["\[Sum]", "k"]\)2^k/((k + 1) (k + 3))], HoldForm[ \!\(\*UnderscriptBox["\[Sum]", "k"]\)(11^k) / (k + 3)!], HoldForm[ \!\(\*UnderscriptBox["\[Sum]", "k"]\)k Sin[k]], HoldForm[ \!\(\*UnderscriptBox["\[Sum]", "k"]\)3^(k - 1) Sin[x/3^k]^3], HoldForm[ \!\(\*UnderscriptBox["\[Sum]", "k"]\)Log[k^2 + 3 k + 1]], HoldForm[ \!\(\*UnderscriptBox["\[Sum]", "k"]\)PolyGamma[2, k]/k^3], HoldForm[ \!\(\*UnderscriptBox["\[Sum]", "k"]\)(k + 5) HarmonicNumber[2 k + 1]], HoldForm[ \!\(\*UnderscriptBox["\[Sum]", "k"]\)k Zeta[3, k + 2]], HoldForm[ \!\(\*UnderscriptBox["\[Sum]", "k"]\)k^2 LerchPhi[5, 2, k + 3]], HoldForm[ \!\(\*UnderscriptBox["\[Sum]", "k"]\)(-u[k]^13 + u[k + 1]^13)]};```
 In[2]:= ```FormulaGallery[forms_List] := Module[{vals = ParallelMap[ReleaseHold, forms]}, Text@TraditionalForm@ Grid[Table[{forms[[i]], "==", vals[[i]]}, {i, Length[forms]}], Dividers -> {{True, False, False, True}, All}, Alignment -> {{Right, Center, Left}, Baseline}, Background -> LightYellow, Spacings -> {Automatic, 2}]]```
 In[3]:= `FormulaGallery[problems]`
 Out[3]=