75816

Appears in sequences

• Let i be in {1,2,3,4} and let r >= 0 be an integer. Let p = {p_1, p_2, p_3, p_4} = {-2,0,1,2}, n=3*r+p_i, and define a(-2)=0. Then a(n)=a(3*r+p_i) gives the quantity of H_(9,4,0) tiles in a subdivided H_(9,i,r) tile after linear scaling by the factor Q^r, where Q=sqrt(x^2-1) with x=2*cos(Pi/9).at n=41A187502
• Numbers with prime factorization pq^3r^6.at n=18A190467
• Integer areas A of integer-sided cyclic quadrilaterals such that the length of the circumradius is a perfect square.at n=14A233315
• Smallest integer k >= 0 such that the maximum digit of k^2 written in factorial base equals n.at n=12A301872
• a(n) = lcm(sigma(n), pod(n)) where sigma(k) = the sum of divisors of k (A000203) and pod(n) = the product of divisors of k (A007955).at n=17A324529
• a(n) = lcm(tau(n), sigma(n), pod(n)) where tau(k) is the number of divisors of k (A000005), sigma(k) is the sum of divisors of k (A000203) and pod(k) is the product of divisors of k (A007955).at n=17A336723
• a(n) is the sum of the entries in an n X n X n 3D matrix whose elements start at 1 in the corner cells and increase by 1 with each step towards the center.at n=17A350236
• Expansion of x / Series_Reversion( x/(1 + 3*x - 6*x^2 - 8*x^3)^(1/3) ).at n=20A370146
• G.f. satisfies A(x) = (1 - 9*x*A(x))^(1/3).at n=10A377268