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A075993 Triangular array T(n,m) = number of integers k such that Floor(n/k)=m. Row n has n terms, for n=1,2,3,... 1
1, 1, 1, 2, 0, 1, 2, 1, 0, 1, 3, 1, 0, 0, 1, 3, 1, 1, 0, 0, 1, 4, 1, 1, 0, 0, 0, 1, 4, 2, 0, 1, 0, 0, 0, 1, 5, 1, 1, 1, 0, 0, 0, 0, 1, 5, 2, 1, 0, 1, 0, 0, 0, 0, 1, 6, 2, 1, 0, 1, 0, 0, 0, 0, 0, 1, 6, 2, 1, 1, 0, 1, 0, 0, 0, 0, 0, 1, 7, 2, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 7, 3, 1, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

The sum of numbers in row n is n.

Number of terms > 0 per row: Sum(A063524(T(n,k)):1<=k<=n} = A055086(n). - Reinhard Zumkeller, Apr 06 2006

LINKS

Table of n, a(n) for n=1..105.

FORMULA

T(n, m)=Floor(n/m)-Floor(n/(m+1)).

EXAMPLE

T(5, 1) = 3 counts k such that Floor(5/k) = 1, namely k = 5, 4, 3. First 6 rows:

1

1 1

2 0 1

2 1 0 1

3 1 0 0 1

3 1 1 0 0 1

CROSSREFS

Columns 1, 2, 3 are essentially A004526, A008615, A008679.

Sequence in context: A168121 A158948 A140224 * A117170 A117466 A136266

Adjacent sequences:  A075990 A075991 A075992 * A075994 A075995 A075996

KEYWORD

nonn,tabl

AUTHOR

Clark Kimberling, Sep 28 2002

STATUS

approved

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Last modified March 31 03:44 EDT 2020. Contains 333136 sequences. (Running on oeis4.)