19153

Appears in sequences

• Triangle read by rows: 4th power of the lower triangular mean matrix (M[i,j] = 1/i for i <= j).at n=18A027448
• Third diagonal of A027448.at n=3A027456
• Brilliant star numbers: semiprimes of the form 6n^2 - 6n + 1 such that both prime factors have the same number of decimal digits.at n=8A083749
• Quadruple lucky numbers (lower terms). Numbers n such that n, n+2, n+6, n+8 are all Lucky numbers.at n=18A139783
• a(n) = 13*n^2 + 10*n + 1.at n=38A161587
• Integers k such that A166100(k)/A005408(k) is not an integer.at n=30A166101
• Centered 12-gonal numbers which are semiprimes, intersection of A003154 and A001358.at n=22A218172
• a(n) = (n-1)! + 1 mod n^3.at n=37A301317
• a(n) is the nearest integer to the area of a triangle with sides prime(n), prime(n+1), prime(n+2).at n=45A338267