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PROJECT EULER · #0544

Chromatic Conundrum

Statement only · UnsolvedOriginal problem ↗

Let F(r,c,n) be the number of ways to colour a rectangular grid with r rows and c columns using at most n colours such that no two adjacent cells share the same colour. Cells that are diagonal to each other are not considered adjacent.

For example, F(2,2,3)=18, F(2,2,20)=130340, and F(3,4,6)=102923670.

Let S(r,c,n)=k=1nF(r,c,k).

For example, S(4,4,15)mod109+7=325951319.

Find S(9,10,1112131415)mod109+7.

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