OFFSET
1,5
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..5000
FORMULA
a(n) = Sum_{j=1..floor((n+1)/2)} j * A023533(n-j+1).
MATHEMATICA
PROG
(Magma)
A023533:= func< n | Binomial(Floor((6*n-1)^(1/3)) +2, 3) ne n select 0 else 1 >;
[(&+[k*A023533(n+1-k): k in [1..Floor((n+1)/2)]]): n in [1..100]]; // G. C. Greubel, Jul 18 2022
(SageMath)
def A023533(n): return 0 if (binomial(floor((6*n-1)^(1/3)) +2, 3)!= n) else 1
[A023868(n) for n in (1..100)] # G. C. Greubel, Jul 21 2022
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
Title simplified by Sean A. Irvine, Jun 12 2019
STATUS
approved