-435

Appears in sequences

• Expansion of tanh(log(1+x)/cosh(x)).at n=6A009787
• Expansion of (1-x)^(-1)/(1+2*x^2+2*x^3).at n=18A077895
• Alternating sum of squares to n.at n=28A089594
• a(n) = sum( (-1)^(r+1)*(n-r)*r, r = 1..floor(n/2) ).at n=58A110422
• Sequence is {a(3,n)}, where a(m,n) is defined at sequence A110665.at n=29A110668
• McKay-Thompson series of class 40d for the Monster group.at n=57A112182
• a(n) = mu(n) * A000217(n).at n=28A125287
• a(n) = 13 + 12*n - n^2.at n=28A136316
• Triangle of coefficients of characteristic polynomials of anti-symmetrical tridiagonal matrices: Middle diagonal: a=1; Lower first subdiagonal: b=2; Upper first subdiagonal: c=-2; Example: M(3) {{1, -2, 0}, {2, 1, -2}, {0, 2, 1}}.at n=31A136643
• Array: row n shows the coefficients of the characteristic polynomial of the n-th principal submatrix of (3i-2 if i=j and = 0 otherwise), as in A204160.at n=17A204161
• Values of n such that L(1) and N(1) are both prime, where L(k) = (n^2+n+1)*2^(2*k) + (2*n+1)*2^k + 1, N(k) = (n^2+n+1)*2^k + n.at n=36A226921
• Expansion of (1 - t)*(1 + t)^x.at n=24A227342
• G.f.: Sum_{n=-oo..+oo} x^(n^2) / (1 - x^n)^n.at n=58A261605
• Expansion of (-5*x^2 + 138*x + 3)/(x^3 - 99*x^2 + 99*x - 1).at n=1A269553
• First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 213", based on the 5-celled von Neumann neighborhood.at n=11A270904
• First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 382", based on the 5-celled von Neumann neighborhood.at n=53A271542
• First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 430", based on the 5-celled von Neumann neighborhood.at n=48A272117
• First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 437", based on the 5-celled von Neumann neighborhood.at n=11A272156
• a(n) = -c(n-1) * c(n-2) * c(n+3) where c(n) = A006769(n).at n=8A278314
• Expansion of r(q^3) / r(q)^3 in powers of q where r() is the Rogers-Ramanujan continued fraction.at n=19A285583