19151

Appears in sequences

• Self-contained numbers: odd numbers k whose Collatz sequence contains a higher multiple of k.at n=5A005184
• Number of fullerenes with 2n vertices (or carbon atoms).at n=28A007894
• a(n) = Sum_{k=1..n} T(k, k-1), where T is the array in A026120.at n=10A026134
• Numbers whose set of base 12 digits is {0,B}, where B base 12 = 11 base 10.at n=11A097258
• Values x for records of the minima of the positive distance d between the ninth power of a positive integer x and the square of an integer y such that d = x^9 - y^2 (x <> k^2 and y <> k^9).at n=26A179791
• Number of (n+2)X3 0..1 arrays with every 3X3 subblock having three equal elements in a row horizontally, vertically, diagonally or antidiagonally exactly three ways, and new values 0..1 introduced in row major order.at n=11A204747
• Number of (n+1)X3 0..2 arrays with the number of rightwards and downwards edge increases in each 2X2 subblock equal to the number in all its horizontal and vertical neighbors.at n=3A205049
• Number of (n+1)X5 0..2 arrays with the number of rightwards and downwards edge increases in each 2X2 subblock equal to the number in all its horizontal and vertical neighbors.at n=1A205051
• T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with the number of rightwards and downwards edge increases in each 2X2 subblock equal to the number in all its horizontal and vertical neighbors.at n=11A205055
• T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with the number of rightwards and downwards edge increases in each 2X2 subblock equal to the number in all its horizontal and vertical neighbors.at n=13A205055
• a(n) = 5^(4n+2) + 5^(3n+2) + 3 * 5^(2n+1) + 5^(n+1) + 1: the right Aurifeuillian factor of 5^(10n+5) - 1.at n=1A220980
• Numbers n such that n^10+10 is prime.at n=30A239347
• Numbers k whose trajectory in the Collatz (or '3x+1') problem includes another multiple of k.at n=11A303698
• Record high points in A336957.at n=51A337646