%I
%S 0,0,0,1,6,25,91,311,1029,3346,10778,34544,110444,352785,1126885,
%T 3601617,11521648,36899528,118322448,379908707,1221423149,3932113059,
%U 12675055399,40909511880,132200481507,427718677728,1385419058692,4492446685542,14582927712740,47385785436719
%N Sum of horizontal positions of the first peak in all bargraphs of semiperimeter n.
%C Horizontal position is xcoordinate of the start of the leftmost horizontal step of the first peak.
%H A. Blecher, C. Brennan, and A. Knopfmacher, <a href="http://dx.doi.org/10.1080/0035919X.2015.1059905">Peaks in bargraphs</a>, Trans. Royal Soc. South Africa, 71, No. 1, 2016, 97103.
%F G.f.: (2*x^3*(x^2sqrt(x^4+2*x^24*x+1)+1)) / ((1x)*(x^2+sqrt(x^4+2*x^24*x+1)2*x+1)^2).
%e For n = 4, a(4) = 1, as only the bargraph with first column of height one and second column of height two has horizontal position 1, all other cases are zero.
%Y Cf. A271941, A273720, A273345.
%K nonn
%O 1,5
%A _Arnold Knopfmacher_, Nov 07 2016
