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A131704 a(1)=1, a(n+1) = Sum_{k=1..floor(sqrt(n))} a(floor(k*sqrt(n))). 0
1, 1, 1, 1, 2, 2, 2, 3, 3, 6, 6, 6, 9, 9, 9, 9, 19, 19, 19, 32, 32, 32, 32, 32, 32, 81, 81, 81, 130, 130, 130, 130, 130, 140, 189, 189, 378, 378, 378, 567, 567, 567, 567, 619, 619, 821, 821, 831, 831, 1711, 1711, 1711, 2591, 2640, 2692, 2881, 2881, 2881, 3761, 3963 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

LINKS

Table of n, a(n) for n=1..60.

MATHEMATICA

a = {1}; Do[AppendTo[a, Sum[a[[Floor[k*Sqrt[n - 1]]]], {k, 1, Floor[Sqrt[n - 1]]}]], {n, 2, 100}]; a (* Stefan Steinerberger, Sep 18 2007 *)

CROSSREFS

Sequence in context: A103600 A267160 A082861 * A124492 A057646 A238892

Adjacent sequences:  A131701 A131702 A131703 * A131705 A131706 A131707

KEYWORD

nonn

AUTHOR

Leroy Quet, Sep 16 2007

EXTENSIONS

More terms from Stefan Steinerberger, Sep 18 2007

STATUS

approved

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Last modified March 26 18:36 EDT 2019. Contains 321511 sequences. (Running on oeis4.)