%I #6 Feb 06 2017 19:02:54
%S 0,0,0,18,144,1196,10122,92280,821038,6991890,58992846,496243152,
%T 4159529298,34612046520,286233965312,2357133355050,19343135795244,
%U 158206906810656,1289891352293998,10487551431195780,85061169561727062,688372469609962898,5559403964257012514
%N Total number of U shapes in all tilings of a 5 X n rectangle with pentominoes of any shape.
%H Alois P. Heinz, <a href="/A247741/b247741.txt">Table of n, a(n) for n = 0..500</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Pentomino">Pentomino</a>
%F a(n) = Sum_{k>0} k * A247708(n,k).
%Y Cf. A174249, A233427, A247708.
%K nonn
%O 0,4
%A _Alois P. Heinz_, Sep 23 2014