415104

Appears in sequences

• exp(sec(x)*arctanh(x))=1+x+1/2!*x^2+6/3!*x^3+21/4!*x^4+120/5!*x^5...at n=9A012840
• sinh(sec(x)*arctanh(x))=x+6/3!*x^3+120/5!*x^5+5376/7!*x^7...at n=4A012846
• Expansion of (eta(q^4) * eta(q^12) / (eta(q) * eta(q^3)))^2 in powers of q.at n=27A123647
• a(n) = Sum_{k=0..floor(n/3)} 2^k * binomial(2*k,2*n-6*k).at n=25A387763