186444716

Appears in sequences

• a(n) = 6*a(n-1) - a(n-2).at n=11A005319
• Numerators of continued fraction convergents to sqrt(18).at n=10A041026
• a(n) = 2*a(n-1) + a(n-2), with a(0) = 1, a(1) = 2, a(2) = 4.at n=22A052542
• a(0)=0; a(1)=1; a(2n) = 4*Sum_{k=0..n} a(2k-1); a(2n+1) = a(2n) + a(2n-1).at n=22A089499
• Expansion of g.f. (1+x)*(3+x)/(1+6*x^2+x^4).at n=21A100434
• A005319 and A002315 interleaved.at n=22A143608
• 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=22A163271
• a(n) = Pell(n)*A001227(n) for n >= 1, where A001227(n) is the number of odd divisors of n.at n=21A209445
• Numerators of the best approximations for sqrt(2).at n=32A331115