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A247740
Total number of T shapes in all tilings of a 5 X n rectangle with pentominoes of any shape.
2
0, 0, 0, 6, 66, 772, 6760, 60122, 552930, 4887052, 42365416, 361418592, 3063883318, 25819450218, 215875963118, 1793852851690, 14833014554258, 122147248758898, 1002084660185318, 8192705916505028, 66777880125812344, 542833111487459532, 4401913323626254612, 35616479684643020150
OFFSET
0,4
LINKS
Wikipedia, Pentomino
FORMULA
a(n) = Sum_{k>0} k * A247707(n,k).
CROSSREFS
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Sep 23 2014
STATUS
approved