33160

Appears in sequences

• Length of n-th term of A022470.at n=36A022471
• Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 91.at n=31A031589
• Number of loopless multigraphs on infinite set of nodes with n edges.at n=10A050535
• a(n) is the total second area moment of all self-avoiding polygons of length 2n on the square lattice.at n=5A056631
• Antidiagonal sums of table A083047.at n=16A083049
• Inverse binomial transform of lucky numbers (A000959).at n=16A123593
• Let spm(n) be the sum of all prime factors of n counted with multiplicities (A001414); sequence gives numbers n such that spm(n+spm(n)) divides both n and n+spm(n).at n=18A131564
• Triangle T(n, k) = coefficients of ( t(n, x) ) where t(n, x) = (1-x)^(n+1)*p(n, x)/x, p(n, x) = x*D( p(n-1, x) ), with p(1, x) = x/(1-x)^2, p(2, x) = x*(1+x)/(1-x)^3, and p(3, x) = x*(1+2*x+x^2)/(1-x)^4, read by rows.at n=47A166345
• Triangle T(n, k) = coefficients of ( t(n, x) ) where t(n, x) = (1-x)^(n+1)*p(n, x)/x, p(n, x) = x*D( p(n-1, x) ), with p(1, x) = x/(1-x)^2, p(2, x) = x*(1+x)/(1-x)^3, and p(3, x) = x*(1+2*x+x^2)/(1-x)^4, read by rows.at n=52A166345
• a(n) = Sum_{d|n} d*2^(n/d)*tau(d).at n=14A174478
• Irregular table read by rows: Take an octagon with all diagonals drawn, as in A333075. Then T(n,k) = number of k-sided polygons in that figure for k >= 3.at n=17A333076