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%I #22 Dec 17 2017 03:08:33
%S 1,1,1,1,1,1,1,1,3,1,1,1,1,1,3,1,1,1,1,1,3,1,1,1,3,1,3,1,1,1,1,1,3,1,
%T 3,1,1,1,3,1,1,1,1,1,3,1,1,1,3,3,3,1,1,1,3,1,3,1,1,1,1,1,5,1,3,1,1,1,
%U 3,3,1,1,1,1,3,1,3,1,1,1,5,1,1,1,3,1,3,1,1,1,3,1,3,1,3,1,1,3,5,1,1,1,1,1,3,1
%N Number of parts in the symmetric representation of sigma(n) in two successive octants of two quadrants.
%C In the diagram of the top view of the pyramid described in A244050 consider a 90-degree sector on two successive octants of two quadrants. The area of the top triangle is equal to 1 and the sum of the areas of all parts (or regions) added at n-th stage equals sigma(n), the sum of the divisors of n.
%C a(n) is also the number of terraces at n-th level (starting from the top) in the mentioned sector of the pyramid.
%C For more information see A237593 and A237270.
%H Antti Karttunen, <a href="/A262619/b262619.txt">Table of n, a(n) for n = 1..5000</a> (computed from the b-file of A237271 provided by Michel Marcus)
%F a(n) = A237271(n), if A237271(n) is odd.
%F a(n) = A237271(n) - 1, if A237271(n) is even.
%Y Cf. A000203, A196020, A235791, A236104, A237270, A237271, A237591, A237593, A244050, A244971, A245092, A262618.
%K nonn
%O 1,9
%A _Omar E. Pol_, Nov 06 2015
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