高校数学の質問スレ（医者・東大卒専用） Part438

Wolfram Language 14.0.0 Engine for Microsoft Windows (64-bit)
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In[1]:= solve[nn_,n_,m_]:=(
ass=Counts[#]& /@ Flatten[Table[Sort /@ IntegerPartitions[x,{n},Range[0,m-1]],{x,m*Range[0,n-1]}],1];
li=KeyValueMap[List,#]& /@ ass;
{q,r}=QuotientRemainder[nn,m];
c=Flatten@{Table[q+1,r],Table[q,m-r]};
m2c[x_] :=(
i=If[x[[1]]==0,m,x[[1]]];
Binomial[c[[i]],x[[2]]]);
cases=Total[Times@@@ (m2c /@ # & /@ li)]; (* cases=Total[Times@@ #&/@ (m2c /@ # & /@ li)];*)
cases/Binomial[nn,n]
)

In[2]:= solve[100,10,5]

4555344594
Out[2]= -----------
22776722969