-1680

Appears in sequences

• Expansion of e.g.f.: sech(sin(x)*log(x+1)).at n=8A012289
• Expansion of Product_{m>=1} (1+q^m)^(-3).at n=25A022598
• Dirichlet inverse of the Jordan function J_2 (A007434).at n=40A046970
• Triangle of nonzero coefficients of Hermite polynomials H_n(x) in increasing powers of x.at n=16A059343
• Triangle read by rows. T(n, k) are the coefficients of the Hermite polynomial of order n, for 0 <= k <= n.at n=29A060821
• Ramanujan's function F_7(q).at n=31A064512
• Sum_{d divides n} d^2*(-1)^bigomega(d), where bigomega(n) = A001222(n).at n=40A076792
• Expansion of (1+4x)/(1+4x+5x^2).at n=9A090133
• Generalized Stirling2 array (-1,2)S2. Irregular triangle a(n, m) for n >= 1 and 2 <= m <= 2*n.at n=21A091752
• Triangle read by rows giving the coefficients of general sum formulas of n-th Lucas numbers (A000204). The k-th row (k>=1) contains T(i,k) for i=1 to 2*k-1, where T(i,k) satisfies L(n) = Sum_{k=1..n} Sum_{i=1..2*k-1} T(i,k) * C(n-k,i-1) * n^(n-k) / (n-1)!.at n=14A101033
• Triangle read by rows: T(n,k) is the coefficient of x^k (0<=k<=n) in the monic characteristic polynomial of the n X n matrix with 3's on the diagonal and 1's elsewhere (n>=1). Row 0 consists of the single term 1.at n=51A103247
• a(n) = Sum[d|n, d==1 (mod 3), d^2] - Sum[d|n, d==2 (mod 3), d^2].at n=40A103440
• Expansion of eta(q)^4 * eta(q^2) * eta(q^6)^5 / eta(q^3)^4 in powers of q.at n=40A111661
• Number triangle whose row sums are the Fibonacci numbers.at n=61A113020
• Expansion of (9*phi(q)*phi(q^3)^5 - phi(q)^5*phi(q^3))/8 in powers of q where phi(q) is a Ramanujan theta function.at n=41A113261
• Cumulant expansion numbers: Coefficients in expansion of log(1 + Sum_{k>=1} x[k]*(t^k)/k!).at n=56A127671
• A scaled version of the coefficient array for orthogonal polynomials defined by C(2n,n).at n=32A128412
• Riordan array ((1-2x)/(1+2x),x/(1+2x)^2).at n=32A128414
• Irregular triangular array a(n,m) for third (k=3) convolution of Chebyshev's S(n,x) = U(n,x/2) polynomials, read by rows (n >=0, 0 <= m <= floor(n/2)).at n=28A128505
• Triangle read by rows: T(n,k) is the coefficient [x^k] of (-1)^n times the characteristic polynomial of the Cartan matrix for the root system D_n.at n=48A129862