67442

Appears in sequences

• Triangle read by rows: T(n,k) is number of hex trees with n edges and level of first leaf (in the preorder traversal) equal to k (1 <= k <= n).at n=46A126186
• Reversals of Lucas numbers (sorted).at n=21A140463
• Number of 2n X 2 0..4 arrays with values 0..4 introduced in row major order and each element equal to an even number of horizontal and vertical neighbors.at n=2A198535
• Number of 2nX6 0..4 arrays with values 0..4 introduced in row major order and each element equal to an even number of horizontal and vertical neighbors.at n=0A198537
• T(n,k)=Number of 2nX2k 0..4 arrays with values 0..4 introduced in row major order and each element equal to an even number of horizontal and vertical neighbors.at n=3A198538
• T(n,k)=Number of 2nX2k 0..4 arrays with values 0..4 introduced in row major order and each element equal to an even number of horizontal and vertical neighbors.at n=5A198538
• Lucas numbers written backwards.at n=21A267551
• Expansion of Product_{k>=1} ((1 + x^(2*k))/(1 - x^(2*k-1)))^k.at n=27A295831
• Number of n X 3 0..1 arrays with every element equal to 2, 3, 6 or 7 king-move adjacent elements, with upper left element zero.at n=21A298141
• Antidiagonal-sums of the absolute value of the array A377051(n,k) = n-th term of k-th differences of powers of primes.at n=18A377053