A174792 - OEIS

%I #10 Jan 07 2019 04:39:54

%S 0,1,1,-7,-15,33,145,-71,-1119,-767,7137,13625,-35567,-138079,97265,

%T 1099385,556609,-7236351,-12231999,37865849,130726193,-122102751,

%U -1075051951,-351058887,7296407521,10828871681,-39894922079,-122993431367,145442151505,1046291093153

%N Expansion of x*(1 - x^2)/(1 - x + 7*x^2 + x^3).

%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (1,-7,-1).

%F G.f.: (1/2)*(x/(1 - x))*g(f(x)), where f(x) = (1 + x)/(-1 + x), and g(x) = (1-x^2)/(1 - x^2 - x^3) is the g.f. of the Padovan sequence A000931.

%F a(n) = a(n-1) - 7*a(n-2) - a(n-3), n >= 4. - _Franck Maminirina Ramaharo_, Jan 06 2019

%t CoefficientList[Series[x*(1 - x^2)/(1 - x + 7*x^2 + x^3), {x, 0, 50}], x]

%o (Maxima) (a[0] : 0, a[1] : 1, a[2] : 1, a[3] : -7, a[n] := a[n-1] - 7*a[n-2] - a[n-3], makelist(a[n], n, 0, 50)); /* _Franck Maminirina Ramaharo_, Jan 06 2019 */

%Y Cf. A000931

%K sign,easy,less

%O 0,4

%A _Roger L. Bagula_, Mar 29 2010

%E Edited by _Franck Maminirina Ramaharo_, Jan 06 2019