login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A123517 Triangle read by rows: T(n,k) = floor(n/k + 1/2) - floor(n/(k + 1/2)) (1<=k<=n). 1
1, 1, 1, 1, 1, 1, 2, 1, 0, 1, 2, 1, 1, 0, 1, 2, 1, 1, 1, 0, 1, 3, 2, 0, 1, 0, 0, 1, 3, 1, 1, 1, 1, 0, 0, 1, 3, 2, 1, 0, 1, 1, 0, 0, 1, 4, 1, 1, 1, 1, 1, 0, 0, 0, 1, 4, 2, 1, 1, 0, 1, 1, 0, 0, 0, 1, 4, 2, 1, 1, 0, 1, 1, 1, 0, 0, 0, 1, 5, 2, 1, 1, 1, 0, 1, 1, 0, 0, 0, 0, 1, 5, 2, 1, 1, 1, 0, 1, 1, 1, 0, 0, 0, 0, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,7

COMMENTS

Row n has sum n.

REFERENCES

B. Chen, C. Kimberling and P. R. Pudaite, Math. Magazine, 77, No. 1, 2004, pp. 70 (Q937), 75 (A937).

LINKS

G. C. Greubel, Table of n, a(n) for the first 50 rows, flattened

MAPLE

T:=proc(n, k) if k<=n then floor(n/k+1/2)-floor(n/(k+1/2)) else 0 fi end: for n from 1 to 16 do seq(T(n, k), k=1..n) od; # yields sequence in triangular form

MATHEMATICA

Table[Floor[n/k + 1/2] - Floor[n/(k + 1/2)], {n, 1, 10}, {k, 1, n}] // Flatten (* G. C. Greubel, Oct 14 2017 *)

PROG

(PARI) for(n=1, 10, for(k=1, n, print1(floor(n/k + 1/2) - floor(n/(k + 1/2)), ", "))) \\ G. C. Greubel, Oct 14 2017

CROSSREFS

Sequence in context: A324667 A258260 A094713 * A178948 A203827 A194289

Adjacent sequences:  A123514 A123515 A123516 * A123518 A123519 A123520

KEYWORD

nonn,tabl

AUTHOR

Emeric Deutsch, Oct 14 2006

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified September 18 23:16 EDT 2021. Contains 347548 sequences. (Running on oeis4.)