This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A244971 #29 May 24 2021 23:32:18
%S A244971 1,1,4,1,4,1,4,1,8,4,4,1,4,4,8,1,4,1,4,1,12,4,4,1,8,4,12,1,4,1,4,1,12,
%T A244971 4,8,1,4,4,12,1,4,1,4,4,8,4,4,1,8,8,12,4,4,1,12,1,12,4,4,1,4,4,16,1,
%U A244971 12,1,4,4,12,8,4,1,4,4,12,4,8,4,4,1,16,4,4,1,12,4,12,1,4,1
%N A244971 Number of regions in the symmetric representation of sigma(n) on the four quadrants.
%C A244971 Partial sums give A244970.
%C A244971 Number of terraces at the n-th level (starting from the top) of the stepped pyramid described in A244050. - _Omar E. Pol_, Apr 20 2016
%H A244971 Antti Karttunen, <a href="/A244971/b244971.txt">Table of n, a(n) for n = 1..5000</a> (computed from the b-file of A237271 provided by Michel Marcus)
%F A244971 a(n) = 1, if A237271(n) = 1.
%F A244971 a(n) = 4*(A237271(n) - 1), if A237271(n) > 1.
%e A244971 From _Omar E. Pol_, Apr 20 2016: (Start)
%e A244971 Illustration of the top view of the stepped pyramid with 16 levels:
%e A244971 . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
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%e A244971 .
%e A244971 Note that the above diagram contains a hidden pattern, simpler, which emerges from the front view of every corner of the stepped pyramid.
%e A244971 For more information about the hidden pattern see A237593.
%e A244971 (End)
%o A244971 (PARI) lista() = {v = readvec("b237271.txt"); for (i=1, #v, vi = v[i]; if (vi == 1, w = 1, w = 4*(vi-1)); print1(w, ", "););} \\ _Michel Marcus_, Sep 29 2014
%Y A244971 Cf. A000203, A196020, A235791, A236104, A237270, A237271, A237591, A237593, A239050, A239660, A239931-A239934, A244050, A244370, A244371, A244970, A245092.
%K A244971 nonn
%O A244971 1,3
%A A244971 _Omar E. Pol_, Jul 08 2014