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A335190 a(n) is the number of values of k < n for which 4*(a(k) + a(n-k)) <= n.

%I A335190 #9 May 27 2020 11:14:15
%S A335190 0,1,0,2,2,1,2,6,2,4,0,5,4,2,6,8,4,7,2,8,6,3,10,12,6,10,4,11,8,4,12,
%T A335190 14,8,13,6,14,10,5,14,18,10,14,8,17,10,10,18,20,14,17,12,20,10,13,16,
%U A335190 22,16,14,14,25,10,14,16,24,22,19,16,28,12,17,20,30,24
%N A335190 a(n) is the number of values of k < n for which 4*(a(k) + a(n-k)) <= n.
%C A335190 This sequence is a variant of A335060.
%C A335190 Graphically, we have an overlay of four curves that correspond to the quadrisections of the sequence.
%H A335190 Rémy Sigrist, <a href="/A335190/b335190.txt">Table of n, a(n) for n = 1..10000</a>
%H A335190 Rémy Sigrist, <a href="/A335190/a335190.png">Colored scatterplot of the first 100000 terms</a>
%e A335190 The first terms, alongside the corresponding k's, are:
%e A335190   n   a(n)  k's
%e A335190   --  ----  ---------------------
%e A335190    1     0  {}
%e A335190    2     1  {1}
%e A335190    3     0  {}
%e A335190    4     2  {1, 3}
%e A335190    5     2  {2, 3}
%e A335190    6     1  {3}
%e A335190    7     2  {1, 6}
%e A335190    8     6  {1, 2, 3, 5, 6, 7}
%e A335190    9     2  {3, 6}
%e A335190   10     4  {1, 3, 7, 9}
%e A335190   11     0  {}
%e A335190   12     5  {1, 3, 6, 9, 11}
%o A335190 (PARI) for (n=1, #a=vector(73), print1 (a[n]=sum(k=1, n-1, a[k]+a[n-k]<=n/4)", "))
%Y A335190 Cf. A335060.
%K A335190 nonn,look
%O A335190 1,4
%A A335190 _Rémy Sigrist_, May 26 2020