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a(n)=(1/361)*[1+20^n*[19*n-1)], with n>=0 [From Paolo P. Lava, Jan 13 2009]
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G.f.: -x / ( (x-1)*(-1+20*x)^2 ). - R. J. Mathar, Nov 07 2015
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<a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (41, -440, 400).
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Harvey P. Dale, <a href="/A014937/b014937.txt">Table of n, a(n) for n = 1..750</a>
a(1)=1, a(2)=41, a(3)=1241, a(n)=41*a(n-1)-440*a(n-2)+400*a(n-3) From Harvey P. Dale, Jun 04 2012
RecurrenceTable[{a[1]==1, a[n]==n*20^(n-1)+a[n-1]}, a, {n, 20}] (* or *) LinearRecurrence[{41, -440, 400}, {1, 41, 1241}, 20] (* Harvey P. Dale, Jun 04 2012 *)
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a(n)=(1/361)*[1+20^n*[19*n-1)], with n>=0 [From _Paolo P. Lava (paoloplava(AT)gmail.com), _, Jan 13 2009]
Olivier Gerard (olivier.gerard(AT)gmail.com)