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A174334
73*n^2.
1
0, 73, 292, 657, 1168, 1825, 2628, 3577, 4672, 5913, 7300, 8833, 10512, 12337, 14308, 16425, 18688, 21097, 23652, 26353, 29200, 32193, 35332, 38617, 42048, 45625, 49348, 53217, 57232, 61393, 65700, 70153, 74752, 79497, 84388, 89425, 94608
OFFSET
0,2
FORMULA
a(n) = (37*n)^2-(36*n)^2.
G.f.: 73*x*(1 + x)/(1 - x)^3. - Vincenzo Librandi, Aug 21 2014
a(n) = 3*a(n-1)-3*a(n-2)+a(n-3) for n>2.
MATHEMATICA
Table[73 n^2, {n, 0, 40}] (* or *) CoefficientList[Series[73 x (1 + x)/(1 - x)^3, {x, 0, 40}], x] (* Vincenzo Librandi, Aug 21 2014 *)
PROG
(Magma) [73*n^2: n in [0..50]];
(Magma) I:=[0, 73, 292]; [n le 3 select I[n] else 3*Self(n-1)-3*Self(n-2)+Self(n-3): n in [1..40]]; // Vincenzo Librandi, Aug 21 2014
(PARI) a(n)=73*n^2 \\ Charles R Greathouse IV, Jun 17 2017
CROSSREFS
Sequence in context: A033244 A140857 A158740 * A142614 A158744 A297430
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Mar 16 2010
EXTENSIONS
Comment rewritten as formula by Bruno Berselli, Jul 12 2012
STATUS
approved