131836323

Appears in sequences

• Pell-Lucas numbers: numerators of continued fraction convergents to sqrt(2).at n=22A001333
• a(0) = 1, a(1) = 3; for n > 1, a(n) = 6*a(n-1) - a(n-2).at n=11A001541
• Numerators of continued fraction convergents to sqrt(8).at n=21A041010
• a(n) is the least natural number m such that the fractional part of m*(2^0.5) is less than 2^(-n).at n=26A058580
• Numbers k such that k^2-1 and k^2 are consecutive powerful numbers.at n=21A060860
• Expansion of (1+x)/(1-2*x-x^2).at n=21A078057
• a(0) = a(1) = 1; thereafter a(2*n+1) = 2*a(2*n) - a(2*n-1), a(2*n) = 4*a(2*n-1) - a(2*n-2).at n=22A079496
• Greedy frac multiples of sqrt(2): a(1)=1, Sum_{n>=0} frac(a(n)*x)=1 at x=sqrt(2).at n=31A079934
• Expansion of g.f. (1+x)*(3+x)/(1+6*x^2+x^4).at n=20A100434
• a(n) = -2*a(n-1) + a(n-2) for n>1, a(0)=1, a(1)=-1.at n=22A123335
• a(n) = 6*a(n-2) - a(n-4) for n > 4, with a(1)=1, a(2)=0, a(3)=3, a(4)=2.at n=22A126354
• Shifted Pell recurrence: a(n) = 2*a(n-2) + a(n-4).at n=41A135246
• Numerators of the upper principal and intermediate convergents to 2^(1/2).at n=21A143609
• 279841n^2 - 165048n + 24335.at n=22A156843
• a(n) = if n even then P((n-2)/2)+P(n/2) otherwise 3*P((n+1)/2)+P((n-1)/2) where P(i) are the Pell numbers (A000129).at n=40A189050
• a(n) = if n even then P((n-2)/2)+P(n/2) otherwise 3*P((n+1)/2)+P((n-1)/2) where P(i) are the Pell numbers (A000129).at n=43A189050
• Numbers such that floor(a(n)^2 / 8) is again a square.at n=23A204514
• Denominators of the best approximations for sqrt(2).at n=32A331101
• Numerators of the best approximations for sqrt(2).at n=31A331115