221943

Appears in sequences

• Odd n such that genus of modular curve X_0(N) is never equal to n.at n=12A054730
• a(n) = Sum_{k=0..2n-1} C(2n-1,k)*trinomial(n,k) for n>0 with a(0)=1.at n=6A132306
• Number of 5Xn 0..1 arrays with every element equal to 0, 2, 3, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.at n=8A303245