1786050

Appears in sequences

• Expansion of e.g.f.: exp(arcsin(x)-arcsinh(x))=1+2/3!*x^3+40/6!*x^6+450/7!*x^7+2240/9!*x^9...at n=11A013416
• arcsin(arcsin(x)-arcsinh(x))=2/3!*x^3+450/7!*x^7+2240/9!*x^9...at n=4A013417
• tan(arcsin(x)-arcsinh(x)) = 2/3!*x^3+450/7!*x^7+4480/9!*x^9...at n=5A013418
• Even refactorable numbers k such that the number r of odd divisors and the number s of even divisors are both odd divisors of k and k is the first number for which the triple (r,s,t) occurs, where t is the number of divisors of k.at n=21A120358
• Triangle of z Transform coefficients from General Pascal [1,10,1} A142459 polynomials multiplied by factor 3^Floor[(2*k - 1)/3].at n=33A167787
• Number of maximal matchings in the n-barbell graph.at n=9A297470
• a(n) = Stirling2(2*n, n)*CatalanNumber(n).at n=5A390277