331695

Appears in sequences

• Expansion of 1/((1-3*x)*(1-12*x)).at n=5A016147
• Odd numbers k such that k and phi(k) have the same number of divisors.at n=7A116518
• Denominators of Blandin-Diaz compositional Bernoulli numbers C_2,n.at n=12A133005
• Least term of A004767 with exactly 2n divisors.at n=27A204086
• Number of n X 7 0..1 arrays with no element equal to more than one of its horizontal and vertical neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.at n=18A280439
• a(n) is the number of n-digit positive integers with exactly two distinct base 10 digits.at n=12A335843
• a(n) is the number of labeled rooted unordered binary trees T where the nodes are labeled with distinct positive integers, the root has label n, each parent label equals the sum of its children labels, and T cannot be extended.at n=40A348850