-894

Appears in sequences

• Triangle read by rows: first define the Narayana numbers: Y(n,m)=Binomial[n, m]*Binomial[n + 1, m + 1]/(n - m + 1); then t(n,m)=Sum[(-1)^j *Y(n + 1, j)*(k + 1 - j)^n, {j, 0, k + 1}].at n=13A155796
• Triangle, read by rows, T(n, k) = Sum_{j=0..k} (-1)^j*(k-j+1)^n*binomial(n+1, j) *binomial(n+2, j)/(j+1).at n=18A176124
• Coefficients in the expansion of ([s] + [2s]x + [3s]x^2 + ...)/([r] + [2r]x + [3r]x^2 + ...); [ ] = floor, r = sqrt(2), s = sqrt(3).at n=40A279628
• Expansion of Sum_{k>=0} (-2)^k * x^(2*k)/Product_{j=1..k} (1 - j * x).at n=10A353261
• Expansion of the 48th root of the series 2*E_2(x) - E_4(x), where E_2(x) and E_4(x) are the Eisenstein series of weight 2 and 4.at n=2A377976