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%I #6 Oct 11 2022 00:50:19
%S 1,120,38966400,335872728576000,23676862831649280000000,
%T 7884265450248813494550528000000,
%U 9001018126678397460727568113336320000000,28542885018291526761600709316931461578752000000000,216619327660243309425808505300579182909935738421248000000000
%N Central terms of triangle A357541: a(n) = A357541(2*n,n).
%C Also equals central terms of triangle A357542: a(n) = A357542(2*n,n).
%o (PARI) {A357541(n, k) = my(S = serreverse( intformal( 1/((1 + x^3)^2*(1 + r^3*x^3)^2 +O(x^(3*n+3)) )^(1/3) )) );
%o (3*n)!*polcoeff( polcoeff((1 + S^3)^(1/3), 3*n, x), 3*k, r)}
%o for(n=0, 15, print1( A357541(2*n, n), ", "))
%Y Cf. A357541, A357542.
%K nonn
%O 0,2
%A _Paul D. Hanna_, Oct 10 2022