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%I #27 Sep 22 2013 16:18:48
%S 0,1,6,15,29,50,80,120,171,235,313,407,517,646,795,965,1158,1374,1616,
%T 1885,2182,2509,2867,3258,3682,4142,4639,5174,5748,6363,7021,7723,
%U 8470,9264,10105,10996,11939,12933,13981,15084,16244,17462,18739,20078,21478,22942
%N Volume of the Johnson square pyramid (rounded down) with all the edge lengths equal to n.
%C Johnson square pyramid: Square base with four equilateral triangular-faces. All the edge lengths are equal to n.
%H K. D. Bajpai, <a href="/A229063/b229063.txt">Table of n, a(n) for n = 1..1000</a>
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Square_pyramid">Square pyramid</a>
%F a(n) = floor(n^3*sqrt(2)/6)
%e a(9)=171: Volume= sqrt(2)/6*n^3= sqrt(2)/6*9^3= 171.8269478 and floor(171.8269478)= 171.
%p A229063 := proc(n)
%p floor(n^3*sqrt(2)/6) ;
%p end proc:
%t Table[Floor[k^3*Sqrt[2]/6],{k,1,100}]
%Y Cf. A228189.
%K nonn
%O 1,3
%A _K. D. Bajpai_, Sep 17 2013
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