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a(n) = n^2 + (n + 1)^3 + (n + 2)^4.
1

%I #16 Sep 08 2022 08:45:03

%S 17,90,287,698,1437,2642,4475,7122,10793,15722,22167,30410,40757,

%T 53538,69107,87842,110145,136442,167183,202842,243917,290930,344427,

%U 404978,473177,549642,635015,729962,835173,951362,1079267,1219650,1373297

%N a(n) = n^2 + (n + 1)^3 + (n + 2)^4.

%H Vincenzo Librandi, <a href="/A061222/b061222.txt">Table of n, a(n) for n = 0..10000</a>

%F G.f.: (2*x^4-7*x^3+7*x^2+5*x+17)/(1-x)^5. - _Zak Seidov_, Oct 02 2010

%e a(1) = 1 + 2^3 + 3^4 = 1 + 8 + 81 = 90.

%t CoefficientList[Normal[Series[(2*x^4-7*x^3+7*x^2+5*x+17)/(1-x)^5,{x,0,20}]],x] (* _Zak Seidov_, Oct 02 2010 *)

%o (Magma) [n^2 + (n + 1)^3 + (n + 2)^4: n in [0..40]]; // _Vincenzo Librandi_, Aug 05 2011

%K easy,nonn

%O 0,1

%A _Olivier Gérard_, May 31 2001

%E Edited by _N. J. A. Sloane_, Jul 19 2009, at the suggestion of _Harry J. Smith_