90972

Appears in sequences

• Composite numbers k+1 such that k*phi(k+1) is a perfect square.at n=41A069068
• a(n) = n*(2*n+1)^2.at n=28A084367
• Smaller member of each exponential amicable pair.at n=0A126165
• Exponential amicable numbers.at n=0A127659
• Integers whose exponential aliquot sequences end in an exponential amicable pair.at n=0A127660
• a(n) = 324*n^2 - 804*n + 468 (n>=2).at n=16A304619
• Number of triadic partitions of the unit square into (2n+1) subrectangles.at n=6A322543
• Lesser member of primitive exponential amicable pairs.at n=0A323753
• Number of unordered quadruples of self-avoiding paths with nodes that cover all vertices of a convex n-gon; one-node paths are allowed.at n=8A360276
• Triangle read by rows: T(n,k) is the number of sets of noncrossing paths of size k that cover n nodes arranged in a circle with one node paths allowed, 0 <= k <= n.at n=49A390894