[go: up one dir, main page]

login
A024595
a(n) = s(1)*t(n) + s(2)*t(n-1) + ... + s(k)*t(n+1-k), where k = floor((n+1)/2), s = (F(2), F(3), ...), t = A023533.
3
1, 0, 0, 1, 2, 3, 5, 0, 0, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987, 1598, 2586, 4184, 6770, 10954, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987, 1597, 2584, 4181, 6765, 10946, 17711, 28658, 46370, 75028, 121398, 196426
OFFSET
1,5
LINKS
FORMULA
a(n) = Sum_{k=1..floor((n+1)/2)} Fibonacci(k+1)*A023533(n-k+1).
MATHEMATICA
A023533[n_]:= If[Binomial[Floor[Surd[6*n-1, 3]] +2, 3] != n, 0, 1];
A024595[n_]:= A024595[n]= Sum[Fibonacci[k+1]*A023533[n+1-k], {k, Floor[(n+1)/2]}];
Table[A024595[n], {n, 100}] (* G. C. Greubel, Jul 14 2022 *)
PROG
(Magma)
A023533:= func< n | Binomial(Floor((6*n-1)^(1/3)) +2, 3) ne n select 0 else 1 >;
[(&+[Fibonacci(k+1)*A023533(n-k+1): k in [1..Floor((n+1)/2)]]): n in [1..100]]; // G. C. Greubel, Jul 14 2022
(SageMath)
def A023533(n):
if binomial( floor( (6*n-1)^(1/3) ) +2, 3) != n: return 0
else: return 1
[sum(fibonacci(k+1)*A023533(n-k+1) for k in (1..((n+1)//2))) for n in (1..100)] # G. C. Greubel, Jul 14 2022
CROSSREFS
KEYWORD
nonn
STATUS
approved