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G.f. A(x) satisfies: 1+x = A(x)^3 + A(x)^4 - A(x)^6.
6

%I #6 Feb 07 2025 14:38:12

%S 1,1,6,87,1544,30669,652387,14535220,334846575,7911062633,

%T 190635605270,4667362377021,115772752576351,2903222873038115,

%U 73481220638826204,1874686187998433232,48159602555272931592,1244712958804985611455,32343121686417402278602,844434166911645229308309

%N G.f. A(x) satisfies: 1+x = A(x)^3 + A(x)^4 - A(x)^6.

%F G.f.: 1 + Series_Reversion(x - 6*x^2 - 15*x^3 - 14*x^4 - 6*x^5 - x^6).

%e G.f.: A(x) = 1 + x + 6*x^2 + 87*x^3 + 1544*x^4 + 30669*x^5 +...

%e Related expansions.

%e A(x)^3 = 1 + 3*x + 21*x^2 + 298*x^3 + 5280*x^4 + 104772*x^5 +...

%e A(x)^4 = 1 + 4*x + 30*x^2 + 424*x^3 + 7509*x^4 + 148968*x^5 +...

%e A(x)^6 = 1 + 6*x + 51*x^2 + 722*x^3 + 12789*x^4 + 253740*x^5 +...

%e where 1+x = A(x)^3 + A(x)^4 - A(x)^6.

%o (PARI) /* From 1+x = A(x)^3 + A(x)^4 - A(x)^6: */

%o {a(n)=local(A=[1, 1]); for(i=1, n, A=concat(A, 0); A[#A]=-Vec(Ser(A)^3+Ser(A)^4-Ser(A)^6)[#A]); A[n+1]}

%o for(n=0, 25, print1(a(n) , ", "))

%o (PARI) /* From Series Reversion: */

%o {a(n)=local(A=1+serreverse(x - 6*x^2 - 15*x^3 - 14*x^4 - 6*x^5 - x^6 + x^2*O(x^n)));polcoeff(A,n)}

%o for(n=0, 25, print1(a(n) , ", "))

%Y Cf. A249926, A249927, A249928, A249930, A249931, A249932.

%K nonn

%O 0,3

%A _Paul D. Hanna_, Nov 27 2014