-516

Appears in sequences

• McKay-Thompson series of class 20c for Monster.at n=62A058558
• Alternating sum sigma(1)-sigma(2)+sigma(3)-sigma(4)+...+((-1)^(n+1))*sigma(n).at n=52A068762
• 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=50A073891
• G.f. satisfies: A(x) = 1/(1 + x*A(x^2)) and also the continued fraction: 1 + x*A(x^3) = [1; 1/x, 1/x^2, 1/x^4, 1/x^8, ..., 1/x^(2^(n-1)), ...].at n=30A101912
• McKay-Thompson series of class 32d for the Monster group.at n=77A112172
• Expansion of psi(-q)/psi(-q^2) in powers of q where psi() is a Ramanujan theta function.at n=45A116498
• Matrix inverse of triangle A122176, where A122176(n,k) = C( k*(k+1)/2 + n-k + 1, n-k) for n>=k>=0.at n=24A121436
• Matrix inverse of triangle A136501, read by rows.at n=15A136502
• Diagonal sums of inverse of Riordan array (1/(1-x^4),x/(1-x^4)).at n=10A156065
• Array: row n shows the coefficients of the characteristic polynomial of the n-th principal submatrix of (f(i,j)), where f(i,j)=(2i-1 if max(i,j) is odd, and 0 otherwise) as in A204173.at n=38A204174
• G.f. A(x) satisfies A(x) = 1 + x / A(x^2).at n=61A218031
• Expansion of (phi(-q)^3 / phi(-q^3))^2 in powers of q where phi() is a Ramanujan theta function.at n=18A229616
• Expansion of Product_{k>=1} (1 - k*x^k) / (1 + x^k).at n=29A269339
• First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 118", based on the 5-celled von Neumann neighborhood.at n=43A270188
• First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 662", based on the 5-celled von Neumann neighborhood.at n=25A273391
• Expansion of Product_{k>=1} 1/(1 + k^2*x^k).at n=9A292165
• Expansion of 1/(1 + x + x/(1 + x^2 + x^2/(1 + x^3 + x^3/(1 + x^4 + x^4/(1 + ...))))), a continued fraction.at n=19A292854
• Expansion of 1/(1 - x*Product_{k>=1} (1 - x^k)).at n=22A299105
• Solution to 1 = Sum_y Product_{k in y} a(k) for each n > 0, where the sum is over all integer partitions of n with an odd number of parts.at n=32A300862
• Expansion of (phi(x)^3 / phi(x^3))^2 in powers of x where phi() is a Ramanujan theta function.at n=18A321465