315840

Appears in sequences

• Theta series of 9-dimensional odd unimodular lattice E_8 + Z.at n=17A071967
• Record gaps between prime quadruplets.at n=29A113404
• a(n) = A152800(n+2,2n+1) for n>=0.at n=9A152802
• Triangle T(n,k) = coefficient of x^n/n! in expansion of (x/cos x)^k/k!.at n=48A188832
• Number of defective (binary) heaps on n elements where seven ancestor-successor pairs do not have the correct order.at n=10A324068
• a(n) is the first term k of A329902 for which A056239(k) = n.at n=30A330743
• Primorial deflation of A133411(n), where A133411(n) is the smallest highly composite number of the form k*a(n-1) where k is an integer greater than 1.at n=30A330744
• Triangular array read by rows: T(n,k) is the number of labeled tournaments on [n] that have exactly k irreducible (strongly connected) components, n >= 0, 0 <= k <= n.at n=30A354607
• Triangle read by rows: T(n,k) is the number of polygons with 2*n sides, of which k run through the center of a circle, on the circumference of which the 2*n vertices of the polygon are arranged at equal spacing, up to rotation and reflection.at n=22A358329
• E.g.f. satisfies A(x) = 1/(1 - x*A(x)^2)^(x*A(x)^2).at n=7A371146