login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 59th year, we have over 358,000 sequences, and we’ve crossed 10,300 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A109593 Sequence and first differences include all odd numbers exactly once. 1
1, 4, 9, 16, 27, 40, 55, 72, 91, 112, 135, 160, 189, 220, 253, 288, 325, 364, 405, 448, 493, 540, 589, 640, 693, 750, 809, 870, 933, 998, 1065, 1134, 1205, 1278, 1353, 1430, 1509, 1590, 1673, 1758, 1845, 1934, 2027, 2122, 2219, 2318, 2419, 2522, 2627, 2734 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

See A005228.

LINKS

Alois P. Heinz, Table of n, a(n) for n = 1..1000

FORMULA

a(n) = n^2 + C*n^(3/2) + O(n), where C = 5/6. According to the simplified model: the sum of n consecutive odd numbers without the odd squares. - Thomas Ordowski, Sep 24 2014

MATHEMATICA

a = {1}; d = 3; k = 1; Do[ While[ Position[a, d] != {}, d += 2 ]; k = k + d; d += 2; a = Append[a, k], {n, 49} ]; a (* Robert G. Wilson v, Sep 28 2005 *)

CROSSREFS

Cf. A005228.

Sequence in context: A195618 A066969 A213495 * A237589 A138981 A138993

Adjacent sequences: A109590 A109591 A109592 * A109594 A109595 A109596

KEYWORD

base,easy,nonn

AUTHOR

Eric Angelini, Aug 30 2005

EXTENSIONS

Corrected and extended by Robert G. Wilson v, Sep 28 2005

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 6 06:19 EST 2022. Contains 358595 sequences. (Running on oeis4.)