%I #7 May 24 2021 00:34:35
%S 0,5,10,19,31,50,75,110,151,205,268,346,434,540,658,797,949,1124,1315,
%T 1532,1765,2027,2308,2620,2952,3318,3706,4131,4579,5066,5579,6134,
%U 6715,7341,7996,8698,9430,10212,11026,11893,12793,13748
%N a(n) = A047881(n) / 2.
%K nonn
%O 0,2
%A _Clark Kimberling_
%E Name corrected by _Sean A. Irvine_, May 23 2021