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PROJECT EULER · #0405

A Rectangular Tiling

Statement only · UnsolvedOriginal problem ↗

We wish to tile a rectangle whose length is twice its width.
Let T(0) be the tiling consisting of a single rectangle.
For n>0, let T(n) be obtained from T(n1) by replacing all tiles in the following manner:

0405_tile1.png

The following animation demonstrates the tilings T(n) for n from 0 to 5:

0405_tile2.gif

Let f(n) be the number of points where four tiles meet in T(n).
For example, f(1)=0, f(4)=82 and f(109)mod177=126897180.

Find f(10k) for k=1018, give your answer modulo 177.

Write-up coming later

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