2209943

Appears in sequences

• a(n) is the unique odd positive solution x of 2^n = 7x^2+y^2.at n=42A077020
• Expansion of (1 + 2*x)/(1 + 3*x + 4*x^2).at n=21A087168
• Lucas and Lehmer numbers with parameters (1 +- sqrt(-7))/2.at n=43A107920
• Row sums of the Riordan array (1-4x+4x^2, x(1-2x)) (A167431).at n=40A167433