217728

Appears in sequences

• Numbers j such that sigma(sigma(j)) = k*j for some k.at n=39A019278
• Let sigma_m (n) be result of applying sum-of-divisors function m times to n; call n (m,k)-perfect if sigma_m (n) = k*n; sequence gives the (2,14)-perfect numbers.at n=0A019291
• Greatest common divisor of multiperfect numbers and their totient.at n=20A098204
• Expansion of (1 + 24*x)^(1/2).at n=5A108734
• The revolver sequence.at n=23A165646
• T(n,k) = Number of n-step self-avoiding walks on a k X k X k X k 4-cube summed over all starting positions.at n=32A188784
• Number of 5-step self-avoiding walks on an n X n X n X n 4-cube summed over all starting positions.at n=3A188788
• a(n) = 2^n*(4^n-3^(n+1)+3*2^n-1)/6.at n=7A228700
• Integer areas of orthic triangles of integer-sided triangles.at n=17A230402
• Integer areas of the intangents triangle of integer-sided triangles.at n=26A231740
• Integer areas A of the integer-sided triangles such that the length of the inradius and the circumradius are both a perfect square.at n=6A232274
• Integer areas of integer-sided triangles where two sides are of square length.at n=37A232461
• Triangular matrix T defined by T = exp(L) where L(n,k) = C(2*n, 2*k+1)/2, as read by rows n >= 0, k=0..n.at n=39A246381
• Numbers m such that Product(1 + p_i) = Product(1 + e_i), where m = Product((p_i)^e_i).at n=29A272858
• Partial products of A206032 (Product_{d|n} sigma(d)).at n=5A280086
• Numbers m that divide sigma(sigma(m) - m) where sigma is the sum of divisors function (A000203).at n=29A300658
• Number of polygon edges formed when connecting all 4n points on the perimeter of an n X n square by infinite lines.at n=10A345650
• Product of the digits of 3^n.at n=14A358271
• a(n) = phi(n^n - n) where phi is the Euler totient function.at n=5A377678