18874368

Appears in sequences

• Expansion of g.f.: (1+x)/(1-8*x).at n=8A003951
• a(n) = 9*2^n.at n=21A005010
• Sums of 2 distinct powers of 8.at n=35A038484
• Total number of leaves (nodes of vertex degree 1) in all labeled trees with n nodes.at n=8A055541
• a(n) = n! * [x^n] W(-x)*(W(-x) + 2)/(W(-x) + 1), where W denotes Lambert's W function.at n=8A061302
• Reciprocal of n terminates with an infinite repetition of digit 8. Multiples of 10 are omitted.at n=5A064567
• Composites of form prime+1 containing a record number of prime factors.at n=17A066617
• Numbers n such that A017666(n)=phi(n).at n=29A069058
• a(n)=(-1)^(n+1)*det(M(n)) where M(n) is the n X n matrix M(i,j)=min(abs(i-j),i).at n=23A080692
• Number of subsets of {1,.., n} containing exactly two primes.at n=27A089822
• a(n) is the least k with n prime factors (counting multiplicity) such that the sum of these n factors divides k. First member of A036844 with n prime factors.at n=22A104465
• a(n) = tau(N), where N = the number obtained as a concatenation of 8712 with itself n times and tau(n) = number of divisors of n.at n=20A110754
• Third smallest number with exactly n prime factors.at n=22A116453
• n*(n-1)*4^n.at n=9A128798
• Triangle T(n,k) formed by the coordination sequences and the number of leaves for trees.at n=53A158497
• a(0)=8, a(n) = 2*a(n-1) + 2^(n-1) for n > 0.at n=20A159696
• Number of reduced words of length n in Coxeter group on 9 generators S_i with relations (S_i)^2 = (S_i S_j)^9 = I.at n=8A165216
• Number of reduced words of length n in Coxeter group on 9 generators S_i with relations (S_i)^2 = (S_i S_j)^10 = I.at n=8A165787
• Number of reduced words of length n in Coxeter group on 9 generators S_i with relations (S_i)^2 = (S_i S_j)^11 = I.at n=8A166367
• Number of reduced words of length n in Coxeter group on 9 generators S_i with relations (S_i)^2 = (S_i S_j)^12 = I.at n=8A166541