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%I #21 Jan 14 2024 02:27:46
%S 1,2,4,8,16,24,40,80,120,200,400,600,1000,2000,3000,5000,10000,15000,
%T 25000,50000,75000,125000,250000,375000,625000,1250000,1875000,
%U 3125000,6250000,9375000,15625000,31250000,46875000,78125000,156250000,234375000,390625000
%N Sequence identical to its third differences in absolute values.
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,5).
%F From _R. J. Mathar_, Mar 23 2010: (Start)
%F a(n) = 5*a(n-3), n>5.
%F G.f.: (3*x^3+6*x^4+4*x^5+1+2*x+4*x^2)/(1-5*x^3). (End)
%F Sum_{n>=0} 1/a(n) = 391/192. - _Amiram Eldar_, Jan 14 2024
%t Join[{1,2,4},LinearRecurrence[{0,0,5},{8,16,24},40]] (* _Harvey P. Dale_, Dec 08 2011 *)
%Y Cf. A131292, A131665, A132158, A132418, A132658.
%K nonn,easy
%O 0,2
%A _Paul Curtz_, May 06 2008
%E Edited by _Charles R Greathouse IV_, Mar 18 2010
%E More terms from _Harvey P. Dale_, Dec 08 2011