19631

Appears in sequences

• a(n) = Sum_{i=0..floor((n+1)/2)} A047080(n,i).at n=17A047083
• Number of non-anti-associative closed binary operations on a set of order n.at n=2A079176
• Odd numbers n for which 19 is the smallest i (>= 1) with Jacobi symbol J(i,n) getting either a value 0 or -1.at n=10A112078
• Members of A038512 of the form k, k+2, k+6, k+8.at n=32A155511
• Least odd number k such that x' = k has n solutions, where x' is the arithmetic derivative (A003415) of x.at n=26A189560
• Number of partitions of n, where the difference between the number of odd parts and the number of even parts is 6.at n=48A240015
• Semiprimes generated by the polynomial 2 * n^2 + 29.at n=24A241554
• G.f.: G(F(x)) is a power series in x consisting entirely of positive integer coefficients such that G(F(x) - x^k) has negative coefficients for k>0, where G(x) = 1 + x*G(x)^3 is the g.f. of A001764 and F(x) is g.f. of A251690.at n=14A251691
• Number of Mersenne number parts in all partitions of n.at n=28A264395
• Take a squarefree semiprime and take the difference of its prime factors. If it is a squarefree semiprime repeat the process. Sequence lists the squarefree semiprimes that generate other squarefree semiprimes only in the first k steps of this process. Case k = 4.at n=39A296811
• Number of nX6 0..1 arrays with every element unequal to 0, 2, 3, 5 or 8 king-move adjacent elements, with upper left element zero.at n=9A305358
• Numbers k such that k and 4k, taken together, contain all digits 1 though 9 at least once.at n=33A346135
• Composite numbers of the form 2*k^2 + 29.at n=24A352949