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%I #10 Sep 08 2022 08:45:11
%S 0,0,26,333,1944,7550,22770,57771,129248,262764,495450,879065,1483416,
%T 2400138,3746834,5671575,8357760,12029336,16956378,23461029,31923800,
%U 42790230,56577906,73883843,95392224,121882500,154237850,193454001
%N a(n) = T(n^3) - T(n^2), where T() are the triangular numbers (A000217).
%H Vincenzo Librandi, <a href="/A085743/b085743.txt">Table of n, a(n) for n = 0..10000</a>
%F a(n) = (n-1)*n^2*(n^3 + n^2 + 1)/2.
%e a(3) = T(3^3) - T(3^2) = T(27) - T(9) = 378 - 45 = 333.
%o (PARI) t(n)=n*(n+1)/2; for(n=0,50,print1(t(n^3)-t(n^2)","))
%o (Magma) [(n-1)*n^2*(n^3+n^2+1)/2: n in [0..40]]; // _Vincenzo Librandi_, Sep 14 2011
%Y Cf. A000217.
%K nonn,easy
%O 0,3
%A _Jon Perry_, Jul 21 2003
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