126648

Appears in sequences

• a(n) = n! * Sum_{k=1..n} H(k)*(n-k)!, where H(k) = Sum_{j=1..k} 1/j.at n=5A109780
• Expansion of phi(q^2) / phi(-q) in powers of q where phi() is a Ramanujan theta function.at n=27A208850
• Expansion of e.g.f. sinh(x*tan(x/2)) (even powers only).at n=6A296854
• Number of free trees of n vertices whose automorphisms are a 2-group.at n=19A309352