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%I #13 Feb 05 2018 03:01:57
%S 1,4,11,28,65,144,303,624,1240,2438,4661,8872,16487,30635,55734,
%T 101618,181751,326608,575790,1022909,1781314,3135130,5402999,9435440,
%U 16106911,27970523,47305236,81807186,137158135,236510661
%N Series for 2nd perpendicular moment of square lattice bond percolation near a wall (eventually goes negative).
%C The 65th term is the first negative term.
%H I. Jensen, <a href="/A056601/b056601.txt">Table of n, a(n) for n = 0..174</a>
%H I. Jensen, <a href="http://www.ms.unimelb.edu.au/~iwan/dirperc/series/sqbx2w.ser">More terms</a>
%K sign
%O 0,2
%A _N. J. A. Sloane_, Aug 27 2000