53340

Appears in sequences

• Number of atoms in a decahedron with n shells.at n=40A004068
• a(n) = Sum_{k=1..n} T(k, k-1), where T is the array in A026120.at n=11A026134
• Number of covers of an unlabeled n-set such that every point of the set is covered by exactly 3 subsets of the cover and that intersection of every 3 subsets of the cover contains at most one point.at n=6A058790
• Group the natural numbers >= 1 so that the n-th group contains n(n+1)/2 numbers and obtain the group sum.at n=13A095166
• a(n) = 441*n^2 - 21.at n=10A145678
• a(n) = 121*n^2 - n.at n=20A157960
• Nonnegative values x of solutions (x, y) to the Diophantine equation x^2+(x+151)^2 = y^2.at n=11A161482
• Number of non-equivalent ways (mod D_2) to select 4 points from n equidistant points on a straight line so that no selected point is equally distant from two other selected points.at n=39A300761
• Array read by antidiagonals: A(n,k) is the number of nonisomorphic T_0 n-regular set multipartitions (multisets of sets) on a k-set.at n=58A331508
• a(n) = [x^n] 6*(8*x^3 + 3*x + 1) / (1 - 4*x)^(7/2).at n=4A344400
• Numbers k such that A380845(k) > 3*k.at n=31A380930