127536

Appears in sequences

• Irregular triangle: p(k, x) = 2*x*p(k-1, x) + (1 - x^2)*p(k-2, x) for even k, p(k, x) = 2*(k-1)*p(k-1, x) - x*p(k-2, x) for odd k.at n=55A123242
• Fixed points of permutations A252022 and A252023.at n=15A252079