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%I #15 Jun 17 2017 03:06:27
%S 1,11,61,211,551,1201,2311,4061,6661,10351,15401,22111,30811,41861,
%T 55651,72601,93161,117811,147061,181451,221551,267961,321311,382261,
%U 451501,529751,617761,716311,826211,948301,1083451
%N Partial sums of A008531, or crystal ball sequence for {A_4}* lattice.
%H Ben Thurston, <a href="/A222408/a222408.png">2-dimensional model of initial terms (cf. A001846)</a>
%H <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (5,-10,10,-5,1).
%F a(n) = (4+10*n+15*n^2+10*n^3+5*n^4)/4. G.f.: -(x^4+6*x^3+16*x^2+6*x+1) / (x-1)^5. [_Colin Barker_, Mar 08 2013]
%o (PARI) a(n)=5*n*(n+1)*(n^2+n+2)/4 \\ _Charles R Greathouse IV_, Mar 08 2013
%Y Cf. A008531, A001846.
%K nonn,easy
%O 0,2
%A _N. J. A. Sloane_, Feb 21 2013
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