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Antidiagonal sums of square array A158825, in which row n lists the coefficients of the n-th iteration of x*C(x), where C(x) is the Catalan function (A000108).
4

%I #2 Mar 30 2012 18:37:16

%S 1,1,2,5,15,52,202,861,3972,19648,103500,577443,3396804,20988116,

%T 135770140,916936351,6449233093,47137434787,357331341987,

%U 2804582808108,22754919576652,190578011064394,1645490708244886,14629351150837605

%N Antidiagonal sums of square array A158825, in which row n lists the coefficients of the n-th iteration of x*C(x), where C(x) is the Catalan function (A000108).

%o (PARI) {a(n)=local(F=serreverse(x-x^2+O(x^(n+1))),G=x,ADS=0); for(k=1,n,G=x;for(i=1,n-k,G=subst(F,x,G));ADS=ADS+polcoeff(G,k));ADS}

%Y Cf. A158825, A158826, A158827, A158828.

%K nonn

%O 1,3

%A _Paul D. Hanna_, Mar 28 2009