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A230501
Floor(Sum(d(k), k=1..n)/n), where d(k) is the number of divisors of k.
2
1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4
OFFSET
1,4
COMMENTS
Except for n=0, a(n) = floor(A006218(n)/n).
MATHEMATICA
Table[Floor[Sum[DivisorSigma[0, k], {k, n}]/n], {n, 100}] (* T. D. Noe, Oct 22 2013 *)
PROG
(Python)
from math import isqrt
def A230501(n): return (-(s:=isqrt(n))**2+(sum(n//k for k in range(1, s+1))<<1))//n # Chai Wah Wu, Oct 23 2023
CROSSREFS
Sequence in context: A076925 A100961 A263206 * A287272 A300287 A226764
KEYWORD
nonn
AUTHOR
Jon Perry, Oct 21 2013
STATUS
approved