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a(n) = p(0,n), where p(x,n) is the strong divisibility sequence of polynomials based on sqrt(5) as in A327322.
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%I #5 Dec 07 2019 01:43:47

%S 1,2,7,26,521,434,13021,8138,36169,813802,8138021,3390842,203450521,

%T 508626302,1695421007,1589457194,127156575521,35321270978,

%U 3178914388021,3973642985026,26490953233507,198682149251302,1986821492513021,413921144273546,49670537312825521

%N a(n) = p(0,n), where p(x,n) is the strong divisibility sequence of polynomials based on sqrt(5) as in A327322.

%C a(n) is a strong divisibility sequence; i.e., gcd(a(h),a(k)) = a(gcd(h,k)).

%e See Example in A327322.

%t c[poly_] := If[Head[poly] === Times, Times @@ DeleteCases[(#1 (Boole[MemberQ[#1, x] || MemberQ[#1, y] || MemberQ[#1, z]] &) /@Variables /@ #1 &)[List @@ poly], 0], poly];

%t r = Sqrt[5]; f[x_, n_] := c[Factor[Expand[(r x + r)^n - (r x - 1/r)^n]]];

%t Flatten[Table[CoefficientList[f[x, n], x], {n, 1, 12}]]; (* A327322 *)

%t Table[f[x, n] /. x -> 0, {n, 1, 30}] (* A329011 *)

%t Table[f[x, n] /. x -> 1, {n, 1, 30}] (* A329012 *)

%t Table[f[x, n] /. x -> 2, {n, 1, 30}] (* A329013 *)

%t (* _Peter J. C. Moses_, Nov 01 2019 *)

%Y Cf. A327320, A327321, A329012, A329013.

%K nonn,easy

%O 1,2

%A _Clark Kimberling_, Nov 23 2019