OFFSET
0,3
FORMULA
EXAMPLE
A(x) = 1 + x + 2*x^2 - 7*x^3 - 58*x^4 + 369*x^5 + 4572*x^6 --++...
series_reversion(x/A(x))/x = 1 + x + 3*x^2 - 65*x^4 + 4998*x^6 -+...
series_reversion(x*A(x))/x = 1 - x + 12*x^3 - 663*x^5 + 70992*x^7 -+...
PROG
(PARI) {a(n)=local(A=[1, 1]); for(i=1, n, if(#A%2==1, A=concat(A, t); A[ #A]=-subst(Vec(serreverse(x/Ser(A)))[ #A], t, 0)); if(#A%2==0, A=concat(A, t); A[ #A]=subst(Vec(serreverse(x*Ser(A)))[ #A], t, 0))); A[n+1]}
CROSSREFS
KEYWORD
sign
AUTHOR
Paul D. Hanna, Jul 19 2006
STATUS
approved