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A095719
a(n) = Sum_{k = 0..floor(n/2)} floor(C(n-k,k)/(k+1)).
2
1, 1, 2, 2, 4, 5, 8, 11, 18, 25, 40, 59, 90, 137, 210, 319, 492, 754, 1164, 1798, 2786, 4317, 6710, 10438, 16266, 25377, 39650, 62013, 97108, 152212, 238822, 375058, 589520, 927365, 1459960, 2300097, 3626211, 5720649, 9030450, 14263675
OFFSET
1,3
COMMENTS
Sums of diagonal entries in A011847.
LINKS
FORMULA
a(n) = Sum_{k=0..floor(n/2)} floor(C(n-k,k)/(k+1)).
MAPLE
a:=n->add(floor(C(n-k, k)/(k+1)), k=0..n/2);
MATHEMATICA
Table[Sum[Floor[Binomial[n-k, k]/(k+1)], {k, 0, n/2}], {n, 40}] (* Harvey P. Dale, Apr 02 2019 *)
PROG
(Magma)
A095719:= func< n | (&+[Floor(Binomial(n-k, k)/(k+1)): k in [0..Floor(n/2)]]) >;
[A095719(n): n in [1..40]]; // G. C. Greubel, Oct 21 2024
(SageMath)
def A095719(n): return sum(binomial(n-k, k)//(k+1) for k in range(n//2+1))
[A095719(n) for n in range(1, 41)] # G. C. Greubel, Oct 21 2024
CROSSREFS
Sequence in context: A274142 A006206 A060280 * A153952 A050364 A078465
KEYWORD
nonn
AUTHOR
Mike Zabrocki, Jul 08 2004
STATUS
approved