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A diagonal of rectangular table A208896: a(n) = A208896(n+1,n).
2

%I #6 Mar 30 2012 18:37:37

%S 1,1,1,3,19,201,3106,64522,1704795,55095601,2115975655,94466053541,

%T 4818194778101,276874057979927,17721751093252740,1251476983229057488,

%U 96724943665929684251,8125833302851782601185,737619034028749204655009,71975174880203583395021875

%N A diagonal of rectangular table A208896: a(n) = A208896(n+1,n).

%C The g.f. of row n, R(n,x), in the rectangular table A208896 satisfies:

%C (1) R(n,x) = 1 + x*R(n,x)^n * [d/dx x/R(n,x)] for n>=0.

%C (2) [x^k] R(n,x)^(k-n+1) = [x^k] R(n,x)^(k-n) for k>=2.

%C The main diagonal in A208896 obeys: A208896(n,n) = 0 for n>=2.

%o (PARI) {a(n)=local(ROW=1+x+x*O(x^n));for(i=0,n,ROW=1+x*ROW^(n+1)*deriv(x/ROW));polcoeff(ROW,n)}

%o for(n=0,21,print1(a(n),","))

%Y Cf. A208896, A208898.

%K nonn

%O 0,4

%A _Paul D. Hanna_, Mar 03 2012