6254320

Appears in sequences

• a(n) = 2*a(n-1) + a(n-3), with a(0)=1 and a(1)=2.at n=20A008998
• Pisot sequences E(4,9), P(4,9).at n=18A020708
• Number of 3 X n 0..1 arrays with no element equal to fewer vertical neighbors than horizontal neighbors, with new values 0..1 introduced in row major order.at n=18A240784
• Expansion of x^2/(1 - 4*x - 4*x^2 - x^3).at n=12A293710