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A192758 Coefficient of x in the reduction by x^2->x+1 of the polynomial p(n,x) defined below in Comments. 2

%I #7 May 04 2014 17:22:41

%S 0,1,2,4,7,13,22,37,61,101,165,269,437,710,1151,1865,3020,4890,7915,

%T 12810,20730,33546,54282,87834,142122,229963,372092,602062,974161,

%U 1576231,2550400,4126639,6677047,10803695,17480751,28284455,45765215

%N Coefficient of x in the reduction by x^2->x+1 of the polynomial p(n,x) defined below in Comments.

%C The titular polynomial is defined recursively by p(n,x)=x*(n-1,x)+floor((n+4)/4) for n>0, where p(0,x)=1. For discussions of polynomial reduction, see A192232 and A192744.

%F Conjecture: G.f.: -x^2 / ( (1+x)*(x^2+1)*(x^2+x-1)*(x-1)^2 ), partial sums of A080239. a(n)-a(n-2) = A097083(n-1). - _R. J. Mathar_, May 04 2014

%t q = x^2; s = x + 1; z = 40;

%t p[0, n_] := 1; p[n_, x_] := x*p[n - 1, x] + Floor[(n + 4)/4] /; n > 0;

%t Table[Expand[p[n, x]], {n, 0, 7}]

%t reduce[{p1_, q_, s_, x_}] :=

%t FixedPoint[(s PolynomialQuotient @@ #1 +

%t PolynomialRemainder @@ #1 &)[{#1, q, x}] &, p1]

%t t = Table[reduce[{p[n, x], q, s, x}], {n, 0, z}];

%t u1 = Table[Coefficient[Part[t, n], x, 0], {n, 1, z}]

%t (* A080239 *)

%t u2 = Table[Coefficient[Part[t, n], x, 1], {n, 1, z}]

%t (* A192758 *)

%Y Cf. A192744, A192232.

%K nonn

%O 1,3

%A _Clark Kimberling_, Jul 09 2011

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Last modified August 9 13:53 EDT 2024. Contains 375042 sequences. (Running on oeis4.)