|
%I #50 May 22 2022 14:05:01
%S 0,0,1,0,3,0,5,0,7,1,9,0,11,3,13,0,15,5,17,0,20,7,21,0,23,9,28,0,27,
%T 11,29,0,36,13,33,1,35,15,44,0,39,17,41,3,52,19,45,0,47,21,60,5,51,23,
%U 54,0,68,25,57,7,59,27,76,0,66,29,65,9,84,31,69,0,71,33,97,11,75,36,77,0
%N Sum of the even-indexed terms in the n-th row of the triangle A196020.
%C Conjecture: indices of zeros give A082662.
%C a(n) is the total number of steps in all even-indexed double-staircases of the diagram of A196020 with n levels.
%C a(n) is also the total number of steps in all even-indexed double-staircases of the diagram described in A335616 with n levels that have at least one step in the bottom level of the diagram.
%C The graph of the sum-of-divisors function A000203 is intermediate between the graph of A353149 and the graph of this sequence (see the Links section). - _Omar E. Pol_, May 13 2022
%H OEIS Plot 2, <a href="https://oeis.org/plot2a?name1=A353154&name2=A000203&tform1=untransformed&tform2=untransformed&shift=0&radiop1=matp&drawlines=true">A353154 vs A000203</a>
%F a(n) = A353149(n) - A000203(n).
%F a(n) = A209246(n) - A353149(n).
%e For n = 15 the 15th row of the triangle A196020 is [29, 13, 7, 0, 1]. The sum of the even-indexed terms is 13 + 0 = 13, so a(15) = 13.
%Y Cf. A000203, A057641, A082662, A196020, A209246, A211343, A235791, A236104, A237591, A237593, A285901, A335616, A347186, A353149.
%K nonn
%O 1,5
%A _Omar E. Pol_, Apr 27 2022
|
