17821440

Appears in sequences

• A triangle of recursive Fibonacci Lah numbers: f(n) = Fibonacci(n)*f(n - 1), L(n, k) = binomial(n-1, k-1)*(f(n)/f(k)).at n=37A137478
• Number of reduced words of length n in Coxeter group on 17 generators S_i with relations (S_i)^2 = (S_i S_j)^5 = I.at n=6A163451
• Numbers with a record number of divisors that have the same value of the Euler totient function (A000010).at n=16A328857
• Indices k of records of low value in the ratios A319696(k)/A000005(k) between the number of distinct values of the Euler totient function applied to the divisors of k and the number of divisors of k.at n=23A328859
• a(n) is the least number k such that A373531(k) = n, or -1 if no such k exists.at n=20A373532