90150

Appears in sequences

• a(n) is the number of numbers k with 2^(n-1) < k <= 2^n having a number of divisors that is a power of 2.at n=17A036539
• Number of collinear triples of distinct points in Zn x Zn with no two on the same "horizontal" or "vertical" line.at n=14A146557
• Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,0,1,4,2 for x=0,1,2,3,4.at n=7A196295
• T(n,k)=Number of nXk 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 3,0,1,4,2 for x=0,1,2,3,4.at n=47A196300
• Triangle read by rows: T(n,k) (0 <= k <= n) = Sum_{i=0..[k/2]} (-1)^i*binomial(k,2*i)*(2*i-1)!!*n^(k-2*i).at n=60A244490
• Array read by antidiagonals: T(n,k) is the number of functions f: X->Y, where X is a subset of Y, |X| = n, |Y| = n+k, such that for every x in X, f(f(x)) != x.at n=71A334014