This site is supported by donations to The OEIS Foundation.

"Email this user" was broken Aug 14 to 9am Aug 16. If you sent someone a message in this period, please send it again.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A072689 Difference between (least square >= n) and (largest square <= n). 1
 0, 3, 3, 0, 5, 5, 5, 5, 0, 7, 7, 7, 7, 7, 7, 0, 9, 9, 9, 9, 9, 9, 9, 9, 0, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 0, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 0, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 0, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(n)=0 iff n is a square. LINKS FORMULA a(n) = A057427(n - A048760(n)) * (A000196(A048760(n))*2 + 1). MATHEMATICA ds[n_]:=Module[{s=Sqrt[n]}, If[IntegerQ[s], 0, 1+2Floor[s]]]; Array[ds, 80] (* Harvey P. Dale, Dec 05 2013 *) CROSSREFS a(n) = A048761(n) - A048760(n). Cf. A000290, A072690. Sequence in context: A217552 A128046 A102899 * A021972 A193451 A244492 Adjacent sequences:  A072686 A072687 A072688 * A072690 A072691 A072692 KEYWORD nonn AUTHOR Reinhard Zumkeller, Jul 02 2002 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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.