18817

Appears in sequences

• a(0) = 1, a(1) = 2, a(n) = 4*a(n-1) - a(n-2).at n=8A001075
• a(2*n) = a(2*n-1) + a(2*n-2), a(2*n+1) = 2*a(2*n) + a(2*n-1); a(0) = a(1) = 1.at n=16A002531
• a(n) = 2*a(n-1)^2 - 1, starting a(0) = 2.at n=3A002812
• a(n) = (1 + a(n-1)*a(n-2))/a(n-3), a(0) = a(1) = a(2) = 1.at n=17A005246
• a(2n)=2*a(2n-2)^2-1, a(2n+1)=2*a(2n)-1, a(0)=2.at n=6A006695
• Numbers k such that any group of k consecutive integers has integral standard deviation (viz. A011944(k)).at n=4A011943
• Numerators of continued fraction convergents to sqrt(12).at n=7A041016
• Numerators of continued fraction convergents to sqrt(48).at n=7A041082
• Numerators of continued fraction convergents to sqrt(147).at n=3A041268
• Numerators of continued fraction convergents to sqrt(192).at n=7A041356
• Numerators of continued fraction convergents to sqrt(588).at n=3A042126
• Numerators of continued fraction convergents to sqrt(768).at n=7A042480
• Shallow diagonal of triangular spiral in A051682.at n=32A081275
• Numbers k such that k^4 = x^3 + y^2 has an integer solution.at n=39A096741
• Number triangle associated to Chebyshev polynomials of first kind.at n=57A101124
• Number triangle associated to Chebyshev polynomials of first kind.at n=73A101124
• Numbers n such that the Diophantine equation (x+2)^3-x^3=2*n^2 has solutions.at n=4A102344
• Expansion of (1+x+5x^2+2x^3) / (1-4x^2+x^4).at n=17A108413
• a(2*n) = A001570(n), a(2*n+1) = A011943(n+1).at n=7A110293
• Interleave denominators and numerators of convergents to sqrt(3).at n=23A140827