47175

Appears in sequences

• a(0) = 1; a(n) = Sum_{0 <= k < n and gcd(k, n) != 1} a(k).at n=33A054251
• (1/2) * number of occurrences of the most frequent volume given in A103659 assumed by triangular pyramids with their 4 vertices chosen from distinct points of an (n+1)X(n+1)X(n+1) lattice cube.at n=2A103660
• Triangle T(n,k) read by rows: T(n,k) = 1 if k=1 or k=n, otherwise T(n,k) = (3*n-3*k+1)*T(n-1,k-1) + (3*k-2)*T(n-1,k).at n=23A142458
• Triangle T(n,k) read by rows: T(n,k) = 1 if k=1 or k=n, otherwise T(n,k) = (3*n-3*k+1)*T(n-1,k-1) + (3*k-2)*T(n-1,k).at n=25A142458
• a(n) = (1/18)*(9*n^2 + 21*n + 10 - 4^(n+2)*(3*n+5) + 10*7^(n+1)).at n=4A142976
• a(n) = A142458(n+5, n). Fifth diagonal of A142458 triangle.at n=2A144381