121501

Properties

Appears in sequences

• phi(n) is equal to the product of the dual prime-power components of n-1 (i.e., A008477(n-1)).at n=8A039783
• E.g.f. satisfies: A(x) = cosh(x) + x*A(x)^2.at n=6A194958
• Value of prime number D for incrementally largest values of minimal y satisfying the equation x^2 - D*y^2 = 3.at n=36A336796
• a(n) = Sum_{k=0..n} binomial(n,k)^7 * (1 - 7*k*(H(k) - H(n-k))), where H(n) is the n-th harmonic number.at n=4A371882
• a(n) = Sum_{k = 0..n} binomial(n, k)^2*binomial(n+k, k)*A108625(n, n-k).at n=4A376462
• Prime numbersat n=11435