19926

Appears in sequences

• Number of partitions of n into parts 3k+1 and 3k+2 with at least one part of each type.at n=48A035620
• Sums of 2 distinct powers of 3.at n=41A038464
• Values of z in positive integer solutions of x^2 + y^5 = z^3, listed in increasing order of z.at n=26A070067
• a(n) = Sum_{i=1..n} LookAndSay(i).at n=27A079664
• G.f. A(x) satisfies: [x^(2n)] A(x)/Catalan(x)^n = A001764(n) = C(3n,n)/(2n+1) and [x^(2n+1)] A(x)/Catalan(x)^n = A001764(n+1) for n>=0, where Catalan(x) is the g.f. of A000108.at n=9A127927
• Expansion of (f(-x)^3 / f(-x^2))^6 - 64 * x * (f(-x^2)^3 / f(-x))^6 in powers of x where f() is a Ramanujan theta function.at n=11A258739
• Numbers n such that the sum of the distinct prime factors of prime(n)-1 and prime(n+1)-1 are the same.at n=14A259562
• E.g.f.: tan(x)/(1+LambertW(-x)).at n=6A277467
• Number of Dyck paths of semilength n such that the maximal number of peaks per level equals two.at n=9A288743
• Dirichlet g.f.: Product_{k>=2} 1 / (1 - k^(-s))^(3^(k-1)).at n=9A344247
• Dirichlet g.f.: Product_{k>=2} (1 + k^(-s))^(3^(k-1)).at n=9A344266
• a(n) = Sum_{k=1..n} k * lcm(k,n).at n=17A344508
• Array read by antidiagonals: T(k,n) is the least positive integer whose sum of base-2 digits is k and sum of base-3 digits is n, or -1 if there is none.at n=53A375258