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a[n_] := Module[{A}, A={1}; For[i=1, i <= n, i++, AppendTo[A, 0]; A[[-1]] = Coefficient[Sum[x^m*((1 + 5*x + x*O[x]^Length[A])^m - x*(A.x^Range[0, Length[A]-1]))^(m+1), {m, 0, Length[A]}], x, Length[A]]]; A[[n+1]]];
Table[a[n], {n, 0, 24}] (* Jean-François Alcover, May 11 2019, from PARI *)
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a(2*n) = (-1 (mod 5), a(2*^n+1) = -1 (mod 5), for n >= 0.
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a(2*n) = 0 1 (mod 5), a(2*n+1) = 4 -1 (mod 5), for n >= 0.
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Paul D. Hanna, <a href="/A325585/b325585.txt">Table of n, a(n) for n = 1..300</a>
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