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A125057 a(n) is the number of positive integers m such that floor(m/d(m)) = n, where d(m) is the number of positive divisors of m. 3
5, 4, 9, 3, 7, 5, 6, 11, 7, 4, 8, 6, 9, 5, 4, 16, 7, 4, 8, 7, 11, 5, 10, 7, 7, 8, 7, 12, 9, 6, 10, 8, 8, 8, 10, 6, 4, 7, 7, 15, 8, 4, 11, 11, 8, 12, 7, 11, 7, 9, 8, 8, 12, 14, 8, 12, 8, 8, 11, 5, 14, 7, 7, 9, 5, 8, 4, 13, 7, 8, 12, 10, 6, 9, 14, 11, 9, 8, 9, 12, 13, 8, 8, 9, 9, 10, 7, 11, 14, 3, 10 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Is a(n) well-defined? Does every positive integer n equal floor(m/d(m)) for some m?

First occurrence of k>2 in A125057: 4,2,1,7,5,11,3,23,8,28,68,54,40,16,251,572,141,???,???,???,529,..., (630). - Robert G. Wilson v, Jan 11 2007.

LINKS

D. W. Wilson, Table of n, a(n) for n = 1..10000

MATHEMATICA

t = Table[Floor[n/DivisorSigma[0, n]], {n, 10^5}]; f[n_] := Length@Select[t, # == n &]; Array[f, 91] (* Robert G. Wilson v *)

CROSSREFS

Cf. A126888, A000005, A126889, A078709, A125056.

Sequence in context: A241420 A077142 A156057 * A021186 A195705 A212878

Adjacent sequences:  A125054 A125055 A125056 * A125058 A125059 A125060

KEYWORD

nonn

AUTHOR

Hugo van der Sanden, Jan 09 2007

EXTENSIONS

Edited by Robert G. Wilson v, Jan 11 2007

STATUS

approved

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Last modified December 9 03:23 EST 2021. Contains 349625 sequences. (Running on oeis4.)