Number of ways, counted up to symmetry, to build a contiguous building with n LEGO blocks of size 3 X 3.

A123832

Number of ways, counted up to symmetry, to build a contiguous building with n LEGO blocks of size 3 X 3.

Terms

    a(0) =1a(1) =7a(2) =227a(3) =9130a(4) =408081a(5) =19274998a(6) =946866202a(7) =47865420384

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