|
| |
|
|
A092364
|
|
n^2*binomial(n,2).
|
|
3
| |
|
|
0, 4, 27, 96, 250, 540, 1029, 1792, 2916, 4500, 6655, 9504, 13182, 17836, 23625, 30720, 39304, 49572, 61731, 76000, 92610, 111804, 133837, 158976, 187500, 219700, 255879, 296352, 341446, 391500, 446865, 507904, 574992, 648516, 728875, 816480
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,2
|
|
|
COMMENTS
| Coefficient of x^2 in expansion of (1+nx)^n.
|
|
|
LINKS
| Index to sequences with linear recurrences with constant coefficients, signature (5,-10,10,-5,1).
|
|
|
FORMULA
| a(n)=n^3*(n-1)/2. Equals A085540/2 - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), May 09 2007 , corrected Mar 10 2011
G.f. -x^2*(4+7*x+x^2) / (x-1)^5 . - R. J. Mathar, Mar 10 2011
|
|
|
MAPLE
| A092364 := proc(n) n^3*(n-1)/2 ; end proc: # R. J. Mathar, Mar 10 2011
|
|
|
MATHEMATICA
| f[n_]:=(n^4-n^3)/2; lst={}; Do[AppendTo[lst, f[n]], {n, 5!}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Dec 04 2009]
|
|
|
PROG
| (PARI) z(n)=n^2*binomial(n, 2); for(i=1, 40, print1(", "z(i)))
|
|
|
CROSSREFS
| Sequence in context: A070600 A100488 A071174 * A071175 A063262 A156223
Adjacent sequences: A092361 A092362 A092363 * A092365 A092366 A092367
|
|
|
KEYWORD
| nonn,easy
|
|
|
AUTHOR
| Jon Perry (perry(AT)globalnet.co.uk), Mar 19 2004
|
| |
|
|
