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%I #21 Mar 06 2020 00:08:26
%S 1,1,1,3,3,4,7,7,9,13,14,17,22,24,28,35,38,43,52,56,63,74,79,88,101,
%T 108,119,134,143,156,174,185,200,221,234,252,276,291,312,339,357,381,
%U 411,432,459,493,517,547,585,612,646,688,718,756,802,836,878,928,966
%N Expansion of 1/((1-x)*(1-x^3)^2*(1-x^5)).
%C A two-way infinite sequences which is palindromic (up to sign). - _Michael Somos_, Mar 21 2003
%H <a href="/index/Tu#2wis">Index entries for two-way infinite sequences</a>
%H <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (1, 0, 2, -2, 1, -2, 1, -2, 2, 0, 1, -1).
%F G.f.: 1 / ((1 - x) * (1 - x^3)^2 * (1 - x^5)).
%F a(-12 - n) = -a(n). a(n) = a(n-1) + 2*a(n-3) - 2*a(n-4) + a(n-5) - 2*a(n-6) + a(n-7) - 2*a(n-8) + 2*a(n-9) + a(n-11) - a(n-12). - _Michael Somos_, Mar 21 2003
%F A029153(n) = a(floor(n/2) - mod(n,2)) = a(A028242(n - 2)). - _Michael Somos_, Mar 21 2003
%o (PARI) {a(n) = if( n<-11, -a(-12 - n), if( n<0, 0, polcoeff( 1 / ((1 - x) * (1 - x^3)^2 * (1 - x^5)) + x * O(x^n),n)))} /* _Michael Somos_, Mar 21 2003 */
%Y Cf. A028242, A028288, A029153.
%K nonn,easy
%O 0,4
%A _N. J. A. Sloane_
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