240318

Appears in sequences

• a(1)=1, a(n) = a(n-1) + n^5 if n odd, a(n) = a(n-1) + n if n is even.at n=11A140163
• Meandric numbers for a river crossing up to 10 parallel roads at n points.at n=14A209622
• E.g.f.: A(x,y) = exp(y)*P(x) - Q(x,y), where P(x) = 1/Product_{n>=1} (1 - x^n/n) and Q(x,y) = Sum_{n>=1} y^n / Product_{k=1..n} (k - x^k).at n=59A249480