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A085540
a(n) = n*(n + 1)^3.
3
0, 8, 54, 192, 500, 1080, 2058, 3584, 5832, 9000, 13310, 19008, 26364, 35672, 47250, 61440, 78608, 99144, 123462, 152000, 185220, 223608, 267674, 317952, 375000, 439400, 511758, 592704, 682892, 783000, 893730, 1015808, 1149984, 1297032, 1457750, 1632960
OFFSET
0,2
FORMULA
a(n) = 2*A092364(n+1). - Zerinvary Lajos, May 09 2007
G.f.: -2*x*(4 + 7*x + x^2)/(x - 1)^5. - R. J. Mathar, Mar 10 2011
a(n) = A085537(n-1). - Eric W. Weisstein, Sep 08 2017
E.g.f.: exp(x)*x*(8 + 19*x + 9*x^2 + x^3). - Stefano Spezia, Jun 10 2023
From Amiram Eldar, Jul 02 2023: (Start)
Sum_{n>=1} 1/a(n) = 3 - Pi^2/6 - zeta(3).
Sum_{n>=1} (-1)^(n+1)/a(n) = Pi^2/12 + 2*log(2) + 3*zeta(3)/4 - 3. (End)
MATHEMATICA
Table[n (n + 1)^3, {n, 0, 40}] (* Vincenzo Librandi, Aug 15 2016 *)
LinearRecurrence[{5, -10, 10, -5, 1}, {0, 8, 54, 192, 500}, 40] (* Harvey P. Dale, May 06 2019 *)
PROG
(Magma) [n*(n+1)^3: n in [0..40]]; // Vincenzo Librandi, Aug 15 2016
CROSSREFS
Cf. A085537 (same sequence with a 0 prepended), A092364.
Sequence in context: A350236 A254951 A085537 * A259546 A355553 A122657
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Jul 05 2003
STATUS
approved