A182428 a(n) = 2n(19-n).

0, 36, 68, 96, 120, 140, 156, 168, 176, 180, 180, 176, 168, 156, 140, 120, 96, 68, 36, 0, -40, -84, -132, -184, -240, -300, -364, -432, -504, -580, -660, -744, -832, -924, -1020, -1120, -1224, -1332, -1444, -1560, -1680, -1804, -1932, -2064, -2200, -2340, -2484, -2632, -2784, -2940, -3100, -3264, -3432, -3604, -3780, -3960, -4144, -4332, -4524, -4720, -4920, -5124

Offset

0,2

Links

Bruno Berselli, Table of n, a(n) for n = 0..1000

B. Khesin and S. Tabachnikov, editors, Memories of Vladimir Arnold, Notices Amer. Math. Soc., 59 (No. 4, 2012), pp. 482-502 (see illustration of Arnold lecturing on page 495).

Index entries for linear recurrences with constant coefficients, signature (3,-3,1).

Formula

G.f.: 4*x*(9-10*x)/(1-x)^3. - Bruno Berselli, May 23 2012

Mathematica

Table[2 n (19 - n), {n, 0, 61}] (* Bruno Berselli, May 23 2012 *)

Prog

(PARI) a(n)=2*n*(19-n) \\ Charles R Greathouse IV, Jun 17 2017

Crossrefs

Sequence in context: A211724 A250771 A068144 * A208128 A260919 A247381

Adjacent sequences: A182425 A182426 A182427 * A182429 A182430 A182431

Keyword

sign,easy

Author

N. J. A. Sloane, Apr 28 2012

Status

approved