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A067086 a(n) = floor(Sum_{k=1..n} 1/k^(1/3)). 2

%I #12 Feb 22 2023 09:08:00

%S 1,1,2,3,3,4,4,5,5,6,6,7,7,7,8,8,9,9,9,10,10,10,11,11,12,12,12,13,13,

%T 13,13,14,14,14,15,15,15,16,16,16,17,17,17,17,18,18,18,18,19,19,19,20,

%U 20,20,20,21,21,21,21,22,22,22,22,23,23,23,23,24,24,24,24,25,25,25,25

%N a(n) = floor(Sum_{k=1..n} 1/k^(1/3)).

%H Harry J. Smith, <a href="/A067086/b067086.txt">Table of n, a(n) for n = 1..1000</a>

%e a(4) = floor(1 + 1/(2^(1/3)) + 1/(3^(1/3)) + 1/(4^(1/3))) = 3.

%t Table[ Floor[ Sum[1/k^(1/3), {k, 1, n} ]], {n, 1, 75} ]

%t Floor[Accumulate[1/CubeRoot[Range[80]]]] (* _Harvey P. Dale_, Feb 22 2023 *)

%o (PARI) { s=0; for (n=1, 1000, s+=1/n^(1/3); write("b067086.txt", n, " ", floor(s)) ) } \\ _Harry J. Smith_, May 12 2010

%Y Cf. A067085.

%K easy,nonn

%O 1,3

%A _Amarnath Murthy_, Jan 07 2002

%E More terms from _Robert G. Wilson v_, Jan 09 2002

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Last modified April 24 22:17 EDT 2024. Contains 371964 sequences. (Running on oeis4.)