18694

Appears in sequences

• Triangle T(n,k) read by rows giving number of labeled mappings (or functional digraphs) from n points to themselves (endofunctions) with exactly k cycles, k=1..n.at n=16A060281
• Number of functions on n labeled nodes whose representation as a digraph has two components.at n=5A065456
• Successive values x such that the Mordell elliptic curve x^3 - y^2 = d has extremal points with quadratic extension over the rationals.at n=7A200656
• Coordinates x of Mordell elliptic curves x^3-y^2 for primary extremal points with quadratic extensions over rationals.at n=5A201047
• Column k=2 of triangle A257673.at n=10A321947
• a(n) is the smallest k such that A363533(k) = n, or -1 if no such k exists.at n=43A363536
• The five digits of a(n) and their four successive absolute first differences are all distinct.at n=4A365257
• Expansion of g.f. A(x) satisfying A(x)^2 = (1+x) * A(x*A(x)) with A(0) = 0.at n=15A367386
• Integers k for which the sum of digits of Fibonacci(k) is a Fibonacci number.at n=25A383045