OFFSET
1,4
COMMENTS
This sequence is a variant of A335060.
Graphically, we have an overlay of four curves that correspond to the quadrisections of the sequence.
LINKS
Rémy Sigrist, Table of n, a(n) for n = 1..10000
Rémy Sigrist, Colored scatterplot of the first 100000 terms
EXAMPLE
The first terms, alongside the corresponding k's, are:
n a(n) k's
-- ---- ---------------------
1 0 {}
2 1 {1}
3 0 {}
4 2 {1, 3}
5 2 {2, 3}
6 1 {3}
7 2 {1, 6}
8 6 {1, 2, 3, 5, 6, 7}
9 2 {3, 6}
10 4 {1, 3, 7, 9}
11 0 {}
12 5 {1, 3, 6, 9, 11}
PROG
(PARI) for (n=1, #a=vector(73), print1 (a[n]=sum(k=1, n-1, a[k]+a[n-k]<=n/4)", "))
CROSSREFS
KEYWORD
nonn,look
AUTHOR
Rémy Sigrist, May 26 2020
STATUS
approved