51006

Appears in sequences

• a(n) = a(n-1) + (n-2)*a(n-2) + a(n-3) starting a(0)=0, a(1)=a(2)=1.at n=12A121956
• Number of Dyck paths of semilength n avoiding the pattern U^4 D^4 U D.at n=30A225691
• Number of nX3 0..1 arrays with every element equal to 1, 2, 3, 5 or 6 king-move adjacent elements, with upper left element zero.at n=7A298384
• T(n,k)=Number of nXk 0..1 arrays with every element equal to 1, 2, 3, 5 or 6 king-move adjacent elements, with upper left element zero.at n=47A298389
• T(n,k)=Number of nXk 0..1 arrays with every element equal to 1, 2, 3, 5 or 6 king-move adjacent elements, with upper left element zero.at n=52A298389
• T(n,k)=Number of nXk 0..1 arrays with every element equal to 1, 2, 3, 5, 6 or 7 king-move adjacent elements, with upper left element zero.at n=47A299307
• T(n,k)=Number of nXk 0..1 arrays with every element equal to 1, 2, 3, 5, 6 or 7 king-move adjacent elements, with upper left element zero.at n=52A299307