27180

Appears in sequences

• Numbers n such that n*5^n - 1 is prime.at n=8A059676
• The number of functions in a finite set that are not obtainable by a composition power of any other function. Similar to A163947, but it excludes self compositions.at n=5A163949
• Potential magic constants of a 10 X 10 magic square composed of consecutive primes.at n=33A192087
• Triangle T(n,k) represents the coefficients of (x^18*d/dx)^n, where n=1,2,3,....at n=18A223520
• The hyper-Wiener index of the nanostar dendrimer defined pictorially as NS[n] in the Z. S. Irani reference.at n=0A224466
• Smallest number k such that prime(n) divides the n-th divisor of k.at n=34A226101
• Expansion of (1 - t)*(1 + t)^x.at n=38A227342
• Triangular array: Row n shows the coefficients of polynomials p(n,x) defined in Comments.at n=47A249057
• Number of Sós permutations of {0,1,...,n}.at n=43A330503
• E.g.f. satisfies A(x) = 1/(1 - x)^(3*A(x)^(1/3)).at n=5A375879