A291562 Central terms of triangle A291560: a(n) = A291560(2*n-1,n) for n>=1.

1, -10, 8694, -61647300, 1734021238950, -136052492985945900, 24163008287867047021500, -8459330090805576230333085000, 5291501479813583484914737466943750, -5495231184920767021604909502973944937500, 8949980571079076055152283884403171536694652500, -21844650683271846600479522545258218405196394185875000, 76989791585920262367039920605319026539360791969735659537500

Offset: 1

Author

Paul D. Hanna, Sep 08 2017

Keywords

• sign

Comments

The e.g.f. G(x,k) of triangle A291560 satisfies: sin(G(x,k)) = k * sin(x).

Programs

PARI

{A291560(n, r) = (2*n-1)! * polcoeff( polcoeff( asin( k*sin(x + O(x^(2*n)))), 2*n-1, x), 2*r-1, k)}
for(n=1, 15, print1(A291560(2*n-1, n), ", "))