-457

Appears in sequences

• a(n) = -a(n-1) - 2*a(n-2).at n=19A001607
• Expansion of e.g.f. cos(sin(x)/cosh(x)), even powers only.at n=3A009051
• Expansion of (1-x-x^N)/((1-x)(1-x^2)(1-x^3)...(1-x^N)) for N = 8.at n=32A060027
• a(1) = 1, a(2n) = a(2n-1) + c(n) and a(2n+1) = a(2n) - p(n), where c(n)=A002808(n) and p(n)=A000040(n) are the n-th composite and n-th prime numbers, respectively.at n=48A073891
• Expansion of (1 + 2*x)/(1 + 3*x + 4*x^2).at n=9A087168
• Abundance values of numbers whose abundance is (+-1) times a prime.at n=31A088006
• Inverse image of primes 2,3,5,7,... under the map Q defined in A095172.at n=61A095174
• Lucas and Lehmer numbers with parameters (1 +- sqrt(-7))/2.at n=19A107920
• Sum(mu(i)*sigma(j): i+j=n), with mu=A008683 and sigma=A000203.at n=58A112964
• Numerators of the coefficients of (x-1)(x-2)... in the interpolating polynomial through the first n primes.at n=16A118210
• Triangle of the numerators of coefficients c(n,k) = [x^k] P(n,x) of some polynomials P(n,x).at n=32A141904
• Row sums of the Riordan array (1-4x+4x^2, x(1-2x)) (A167431).at n=16A167433
• First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 99", based on the 5-celled von Neumann neighborhood.at n=11A270159
• G.f. satisfies: A(x) = (1 + x) * Product_{k>0} A(x^(2*k)) / Product_{k>1} A(x^(2*k-1)).at n=61A321325