19005

Appears in sequences

• Odd numbers with exactly 4 distinct palindromic prime factors.at n=5A046406
• n satisfying sigma(n+1) = sigma(n-1).at n=25A055574
• Numbers that are sums of 2 or more consecutive squares in more than 1 way.at n=25A062681
• Numbers k such that sigma(k-1) divides sigma(k+1).at n=30A067130
• One-sixth the area of the smallest primitive d-arithmetic triangle, where d=A072330(n).at n=34A072360
• Numbers that are the sum of one or more consecutive squares in more than one way.at n=31A130052
• Numbers k such that k and k+1 have 4 distinct prime factors.at n=24A140078
• Triangle read by rows: T(n,k) is the number of partial bijections (or subpermutations) of an n-element set of height k (height(alpha) = |Im(alpha)|) and with exactly 1 fixed point.at n=25A144090
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, 0, 0), (-1, 1, -1), (1, 0, -1), (1, 0, 1)}.at n=9A149126
• Number of nX5 arrays of occupancy after each element stays put or moves to some horizontal or antidiagonal neighbor.at n=1A221123
• T(n,k)=Number of nXk arrays of occupancy after each element stays put or moves to some horizontal or antidiagonal neighbor.at n=16A221125
• Number of 2 X n arrays of occupancy after each element stays put or moves to some horizontal or antidiagonal neighbor.at n=4A221126
• Numbers n such that sigma(n+1) - sigma(n-1) = k*n for some integer k, where sigma(n) = A000203 (sum of divisors of n).at n=26A223137
• Numbers k such that sigma(k+1) divides sigma(k-1).at n=26A227304
• Number of (n+1)X(2+1) 0..2 arrays with the maximum plus the upper median minus the lower median minus the minimum of every 2X2 subblock equal.at n=3A236887
• Number of (n+1)X(4+1) 0..2 arrays with the maximum plus the upper median minus the lower median minus the minimum of every 2X2 subblock equal.at n=1A236889
• T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with the maximum plus the upper median minus the lower median minus the minimum of every 2X2 subblock equal.at n=11A236893
• T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with the maximum plus the upper median minus the lower median minus the minimum of every 2X2 subblock equal.at n=13A236893
• Triangle read by rows: T(n,k) is the number of n-tuples with sum k + n whose i-th element is a positive integer <= prime(i), 0 <= k < A070826(n).at n=63A239738
• Partial sums of number of overpartitions (A015128).at n=19A277643