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A128437
a(n) = floor((numerator of H(n))/n), where H(n) = Sum_{k=1..n} 1/k is the n-th harmonic number.
2
1, 1, 3, 6, 27, 8, 51, 95, 792, 738, 7610, 7168, 88153, 83695, 79717, 152284, 2478954, 793016, 14489252, 2791756, 898002, 867872, 19318117, 56159289, 1362100898, 1322913164, 11575416740, 11264449603, 318174017634, 310156094338
OFFSET
1,3
COMMENTS
Numerator of H(n) is a(n)*n + A126083(n).
LINKS
EXAMPLE
a(6) = 8 because H(6) = 49/20 and floor(49/6) = 8.
MAPLE
H:=n->sum(1/k, k=1..n): a:=n->floor(numer(H(n))/n): seq(a(n), n=1..35); # Emeric Deutsch, Mar 22 2007
MATHEMATICA
seq = {}; s = 0; Do[s += 1/n; AppendTo[seq, Floor[Numerator[s]/n]], {n, 1, 30}]; seq (* Amiram Eldar, Dec 01 2020 *)
PROG
(PARI) a(n) = numerator(sum(k=1, n, 1/k))\n; \\ Michel Marcus, Feb 01 2019
(Python)
from sympy import harmonic
def A128437(n): return harmonic(n).p//n # Chai Wah Wu, Sep 27 2021
CROSSREFS
KEYWORD
nonn
AUTHOR
Leroy Quet, Mar 03 2007
EXTENSIONS
More terms from Emeric Deutsch, Mar 22 2007
STATUS
approved