login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A058373 a(n) = (1/6)*(2*n - 3)*(n + 2)*(n + 1). 7
0, 0, -1, -1, 2, 10, 25, 49, 84, 132, 195, 275, 374, 494, 637, 805, 1000, 1224, 1479, 1767, 2090, 2450, 2849, 3289, 3772, 4300, 4875, 5499, 6174, 6902, 7685, 8525, 9424, 10384, 11407, 12495, 13650, 14874, 16169, 17537, 18980, 20500, 22099 (list; graph; refs; listen; history; text; internal format)
OFFSET

-2,5

COMMENTS

For n>=0, real parts of sum_(k=0)^n (k+i)^2, where i=sqrt(-1). [Bruno Berselli, Jan 24 2014]

LINKS

Table of n, a(n) for n=-2..40.

FORMULA

a(n) = 2*C(n+2,3) - C(n+2,2). - Zerinvary Lajos, Nov 25 2006

MAPLE

seq((2*n-3)*(n+2)*(n+1)/6, n=-2..40);

MATHEMATICA

s=0; lst={0, s}; Do[s+=n^2-1; AppendTo[lst, s], {n, 0, 6!, 1}]; lst (* Vladimir Joseph Stephan Orlovsky, Nov 07 2008 *)

CROSSREFS

Cf. A236377: real part of sum_(k=0)^n (k + i^k)^2, i=sqrt(-1). [Bruno Berselli, Jan 25 2014]

Sequence in context: A270822 A248117 A305600 * A167386 A027719 A254709

Adjacent sequences:  A058370 A058371 A058372 * A058374 A058375 A058376

KEYWORD

sign,easy

AUTHOR

N. J. A. Sloane, Dec 18 2000

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.

License Agreements, Terms of Use, Privacy Policy .

Last modified July 16 23:38 EDT 2018. Contains 312693 sequences. (Running on oeis4.)