79570260

Appears in sequences

• a(n) = 2*a(n-1) + 2*a(n-3) + a(n-4), with a(0)=1, a(1)=2, a(3)=4, a(4)=10.at n=21A089928
• 2*A084158 (twice Pell triangles).at n=11A114620