20464

Appears in sequences

• Numbers whose set of base-11 digits is {1,4}.at n=43A032823
• Let (u1,u2) be successive untouchable numbers such that phi(u1) = phi(u2); sequence gives values of u2.at n=40A048190
• a(n+3) = 3*a(n+2) - 2*a(n+1) + 1 with a(0)=1, a(1)=5.at n=12A094002
• a(1)=1, a(n) = a(n-1) + n^5 if n odd, a(n) = a(n-1) + n^3 if n is even.at n=6A135099
• Expansion of (1-3*x+6*x^2-3*x^3)/((1-x)^2*(1-2*x)).at n=13A188589
• a(n) = gpf(a(n-3))*gpf(a(n-2)) + gpf(a(n-1)), with a(1)=a(2)=1 and a(3)=2 and where gpf(n) is the greatest prime dividing n, A006530(n).at n=47A258804
• Numbers k such that A001156(k) is divisible by k.at n=7A304046
• The number of flips to go from Hamiltonian cycle beta_n to gamma_n in the Cameron graph of size n using Thomason's algorithm.at n=6A332751
• a(0) = 1; a(n) = (n!)^3 * Sum_{k=0..n-1} a(k) / (k! * (n-k))^3.at n=4A336259
• Numbers k whose decimal representation can be split in three parts which can be used as seeds for a tribonacci-like sequence containing k itself.at n=25A383230