75735

Appears in sequences

• Total number of self-dual binary codes of length 2n. Totally isotropic spaces of index n in symplectic geometry of dimension 2n.at n=5A028362
• Numerator of n * Product_{d|n} (1 + 1/d).at n=31A029933
• Related to triple factorial numbers 2*A034000(n+1).at n=6A034164
• Partial sums of second pentagonal numbers with even index (A049453).at n=33A051895
• Coefficients of the solution to a functional equation.at n=37A092421
• Odd doubly abundant numbers (A125639).at n=5A129087
• a(1) = 1, and then a(n) is sum of k*a(k) where k<n and k divides n.at n=63A165552
• a(n) = Sum_{0<j<n} n^3-j^3.at n=16A206808
• Number of Type I (singly-even) self-dual binary codes of length 2n.at n=5A269455
• First term of n-th difference sequence of (floor(k*r)), r = sqrt(2), k >= 0.at n=19A325664
• Terms of A326835 having more divisors than any smaller term.at n=15A348198
• Numbers k such that A360327(k) > 2*k.at n=8A360328
• T(n,m) is the number of m-dimensional isotropic subspaces of a 2n-dimensional symplectic space over Z/2, n >= 0 and 0 <= m <= n.at n=20A368493