A359026 Number of inequivalent tilings of a 10 X n rectangle using integer-sided square tiles.
1, 1, 51, 347, 7048, 130125, 2551794, 49828415
Offset: 0
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a(3)=7 as the nature of basic blocks requires that the tiling cannot be split vertically into smaller tilings. Thus there needs to be one 2 X 2 tile whose lower left corner is in column 1 and one whose llc is in column 2. There are 7 ways to place these two 2 X 2 tiles.
f[ {A_, B_} ] := Module[ {til = A, basic = B}, {Flatten[ Append[ til, ListConvolve[ A, B ] ]], AppendTo[ basic, B[[ -1 ]] + B[[ -2 ]] + B[[ -3 ] ]]} ]; NumOfBasicBlocks[ n_ ] := Nest[ f, {{1, 1, 8, 28, 117, 472, 1916, 7765}, {1, 7, 13, 20, 35, 66, 118, 218}}, n-2 ][[ 2 ]] NumOfBasicBlocks[ 30 ] LinearRecurrence[{1,1,1},{1,7,13,20,35,66,118,218},40] (* Harvey P. Dale, Dec 06 2018 *)
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