-2208

Appears in sequences

• a(n) = Sum_{d|n, d == 1 mod 4} d^2 - Sum_{d|n, d == 3 mod 4} d^2.at n=46A002173
• Dirichlet inverse of the Jordan function J_2 (A007434).at n=46A046970
• Sum_{d divides n} d^2*(-1)^bigomega(d), where bigomega(n) = A001222(n).at n=46A076792
• a(n) = Sum[d|n, d==1 (mod 3), d^2] - Sum[d|n, d==2 (mod 3), d^2].at n=46A103440
• Expansion of eta(q)^4 * eta(q^2) * eta(q^6)^5 / eta(q^3)^4 in powers of q.at n=46A111661
• 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=47A113261
• Expansion of 1 - (1/3) * b(q) * b(q^2) * c(q)^2 / c(q^2) in powers of q where b(), c() are cubic AGM functions.at n=46A132001
• Triangle read by rows: E. F. Cornelius Jr. and Phill Schultz-based polynomials for the D_n Cartan Matrices in sequence A129862 that give a triangular sequence.at n=16A135185
• Expansion of q^(-1/2) * (eta(q)^4 * eta(q^4)^2 / eta(q^2)^3)^2 in powers of q.at n=23A138502
• Expansion of ((phi(q) * phi(-q^2)^2)^2 - 1) / 4 in powers of q where phi() is a Ramanujan theta function.at n=46A138505
• Expansion of (8 / 7) * (1 - eta(q)^7 / eta(q^7)) - 7 * (eta(q) * eta(q^7))^3 in powers of q.at n=46A138810
• Apply partial sum operator twice to A000594.at n=8A144249
• Irregular triangle, T(n, k) = [x^k] p(n, x), where p(n, x) = 4*Sum_{j=0..n} A008292(n+1, j) * (x/2)^j * (1-x/2)^(n-j), read by rows.at n=29A147563
• Expansion of (b(q^3)^3 - b(q)^3) / 9 in powers of q where b() is a cubic AGM theta function.at n=46A181905
• Array: row n shows the coefficients of the characteristic polynomial of the n-th principal submatrix of f(i,j) = gcd(i+1, j+1) (A204030).at n=21A204111
• A signed triangle of V. I. Arnold for the Springer numbers (A001586).at n=22A256679
• Expansion of Product_{k>=1} 1/(1 + x^k)^(k+1).at n=29A305628