-377

Appears in sequences

• a(n+2) = -a(n+1) + a(n) (signed Fibonacci numbers) with a(-2) = a(-1) = 1; or Fibonacci numbers (A000045) extended to negative indices.at n=16A039834
• a(n) = (-1)^(n-1)*(a(n-1) - a(n-2)), a(1)=1, a(2)=1.at n=30A051792
• a(n) = (-1)^(n-1)*(a(n-1) - a(n-2)), a(1)=1, a(2)=1.at n=33A051792
• Generalized sum of divisors function: third diagonal of A060184.at n=54A060186
• A measure of how close the golden ratio is to rational numbers.at n=28A066212
• A measure of how close the golden ratio is to rational numbers.at n=57A066212
• Let u(1)=u(2)=u(3)=1, u(n)=sign(u(n-1)-u(n-2))/(u(n-3)+1); then a(n) is the numerator of u(n).at n=82A076898
• Let u(1)=u(2)=u(3)=1, u(n)=sign(u(n-1)-u(n-2))/(u(n-3)+1); then a(n) is the numerator of u(n).at n=83A076898
• a(n) = (n+1)*(2-n)/2.at n=28A080956
• (1,1) entry of powers of the orthogonal design shown below.at n=6A090592
• Array T(r,c) read by antidiagonals: values of triangle A098493 interpreted as polynomials, r >= 0.at n=69A098495
• Expansion of (1-x)*(1-x+x^2)/(1-3*x+4*x^2-2*x^3+x^4).at n=14A105371
• Expansion of (x-1)*(x+1) / (8*x^2 + 1 - 3*x + x^4 - 3*x^3).at n=6A108196
• A characteristic triangle for the Fibonacci numbers.at n=34A110033
• Row sums of number triangle related to the Jacobsthal numbers.at n=14A110325
• Riordan array (1/(1+2*x), x*(1+x)/(1+2*x)^2).at n=24A123876
• Said to have been posted at the web site mturk.amazon.com as a puzzle.at n=7A124170
• a(n) = -n^2 + 9*n + 23.at n=25A126719
• First differences of A135992.at n=14A135994
• Triangle read by rows of coefficients of Chebyshev-like polynomials P_{n,6}(x) with 0 omitted (exponents in increasing order).at n=24A136398