18255

Appears in sequences

• Numbers k that divide the (left) concatenation of all numbers <= k written in base 19 (most significant digit on left).at n=43A029488
• Least term in period of continued fraction for sqrt(n) is 9.at n=17A031433
• Numbers k such that 5*2^k + 7 is prime.at n=25A059748
• Numbers k such that the smoothly undulating palindromic number (31*10^k - 13)/99 is a prime.at n=6A062216
• Integer part of log(n^n)^(1 + log(1 + log(1 + n))).at n=20A062451
• Nearest integer to log(n^n)^(1 + log(1 + log(1 + n))).at n=20A062452
• Number of partitions of n such that multiplicities of parts are divisors of n.at n=43A100932
• a(n) = 81*n^2 + 2*n.at n=14A177099
• Number of nonempty subsets of {1, 2, ..., n} with <=5 pairwise coprime elements.at n=31A187266
• Number of 4 X n binary arrays without the pattern 0 1 diagonally, vertically, antidiagonally or horizontally.at n=26A188555
• a(n) = A273059(4n+1).at n=23A275917
• G.f.: 1 + Sum_{n>=1} a(n)*x^n/(1 - x^n) = Product_{n>=1} (1 + n*x^n).at n=20A300278
• One-half of the number of lines through at least 2 points of an n X n grid of points.at n=20A331780
• a(n) = Sum_{k=0..floor(n/4)} 2^k * binomial(n-3*k,k)^2.at n=16A387508