426888

Appears in sequences

• Number of walks of length n on square lattice, starting at origin, staying in first quadrant.at n=11A005566
• Triangle of numbers of square lattice walks that start and end at origin after 2k steps and contain exactly r steps to the east, not touching origin at intermediate stages.at n=30A068218
• Triangle of numbers of square lattice walks that start and end at origin after 2k steps and contain exactly r steps to the east, not touching origin at intermediate stages.at n=33A068218
• Binomial(n-k-1,k) * binomial(n-k,k+1) where k = ceiling(n/4).at n=17A171006
• Numbers with prime factorization p^2*q^2*r^2*s^3 where p, q, r, and s are distinct primes.at n=7A190382
• Norm of coefficients in g.f. C(x) that satisfies: C(x) = 1 + x/C(I*x).at n=25A193384
• a(n) = n^4/8 if n is even, a(n) = (n^2-1)^2/8 if n is odd.at n=43A212892
• Sum of cubes of the first n even numbers (A016743).at n=21A254371
• Triangle T(n,m) = C(2*n,m)*C(2*n-1,n), 0 <= m <= 2*n, n >= 0.at n=42A320327
• Numbers having exactly four non-unitary prime factors.at n=18A338541
• Triangle read by rows: T(n,k) = number of vertices of degree k in an origami flip graph OFG(A2n).at n=50A352880
• a(n) = binomial(2*n, n) * binomial(2*n - 1, n).at n=6A361877
• Triangle read by rows. T(n, k) = (n - k + 1) * binomial(n + k + 1, 2*k)^2 / (n + k + 1).at n=39A370233