2623476242

Appears in sequences

• a(n) = 2*a(n-1) + a(n-2), with a(0) = 1, a(1) = 2, a(2) = 4.at n=25A052542
• Numbers k such that 2*k^2 - 4 is a square.at n=12A075870
• Numerators of the upper principal and intermediate convergents to 2^(1/2).at n=24A143609
• Numerators of fractions in a 'zero-transform' approximation of sqrt(2) by means of a(n) = (a(n-1) + c)/(a(n-1) + 1) with c=2 and a(1)=0.at n=25A163271
• a(n) = Pell(n)*A033719(n) for n>=1, with a(0)=1, where A033719 lists the coefficients in theta_3(q)*theta_3(q^7).at n=25A209454
• a(n) = Pell(n)*A002652(n) for n>=1, with a(0)=1, where A002652 lists the coefficients in theta series of Kleinian lattice Z[(-1+sqrt(-7))/2].at n=25A209455