257114

Appears in sequences

• a(n) = floor(Fibonacci(n)/2).at n=29A004695
• a(n) = Sum_{k=0..floor(n/4)} binomial(n-2k,2k).at n=28A005252
• a(n) = Sum_{1<=k<=n, gcd(k,n)=1} Fibonacci(k).at n=26A070964
• First member of the Diophantine pair (m,k) that satisfies 5*(m^2 + m) = k^2 + k; a(n) = m.at n=9A077259
• A Fibonacci convolution.at n=28A094686
• A transform of (1-x)/(1-2x).at n=26A099517
• a(n) = F(3) + F(6) + F(9) + ... + F(3n), F(n) = Fibonacci numbers A000045.at n=9A099919
• Define a(1)=0, a(2)=2 then a(n) = 3*a(n-1) - a(n-2), a(n+1) = 3*a(n)-a(n-1) and a(n+2) = 3*a(n+1) - a(n) + 2.at n=13A105073
• Antidiagonal sums of number triangle A086645.at n=14A108479
• Expansion of (1-x)^3/(1-4x+5x^2-4x^3+x^4).at n=14A109961
• a(n+3) = 3*a(n+2) + 5*a(n+1) + a(n), a(0) = 1, a(1) = 2, a(2) = 11.at n=9A110679
• a(n) = (A000045(n)-A173432(n))/2.at n=28A173434
• a(2k) = floor(F(k)/2), a(2k+1) = ceiling(F(k)/2), where F = A000045 is the Fibonacci sequence.at n=58A173673
• Partial sums of odd Fibonacci numbers (A014437).at n=17A174542
• a(n) = ((F(n-1)+F(n-2))-1)/2 if F(n) is odd, otherwise a(n) = ((F(n-1)+F(n-2))-2)/2, where F(n) = A000045(n) is the n-th Fibonacci number.at n=28A201864
• x-values in the solutions to x^2 + x = 5*y^2 + y.at n=5A257939
• a(n) = a(n-1) + a(n-2) - a(n-3) + a(n-4) for n > 4, where a(n)=0 for n < 4 and a(4) = 1.at n=31A293014
• a(n) is the integer k that minimizes |k/Fibonacci(n) - 1/2|.at n=29A293505
• Expansion of 1/( (1 + x) * (1 - x^2*(1 + x)^2) ).at n=29A375372