109216786

Appears in sequences

• Companion Pell numbers: a(n) = 2*a(n-1) + a(n-2), a(0) = a(1) = 2.at n=21A002203
• Numerators of continued fraction convergents to sqrt(8).at n=20A041010
• Numerators of continued fraction convergents to sqrt(200).at n=6A041370
• Numbers k such that (k^2 + 4)/2 is a square.at n=10A077444
• Duplicate of A077444.at n=10A077461
• a(n) = floor((1+sqrt(2))^n).at n=21A080039
• a(n) = 14*a(n-1) + a(n-2), starting with a(0) = 2 and a(1) = 14.at n=7A090300
• Expansion of (1+x^2)/(1-2*x-x^2).at n=21A099425
• a(n) = -(u^n-1)*(v^n-1) with u = 1+sqrt(2), v = 1-sqrt(2).at n=20A129744
• a(1) = 2, a(2) = 8; a(n) = 2 a(n - 1) + a(n - 2) - 4*(n mod 2).at n=20A162484
• G.f.: Product_{n>=1} (1 - A002203(n)*x^n + (-1)^n*x^(2*n)) where A002203(n) is the companion Pell numbers.at n=23A204382
• a(n) = n^7 + 7*n^5 + 14*n^3 + 7*n.at n=14A261540