18237

Appears in sequences

• 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 90.at n=27A031588
• Composite numbers n such that 8*n^2-2*n-1 divides the primitive part U(n) of Fibonacci(n).at n=38A159234
• Number of binary strings of length n with no substrings equal to 0000, 0101, or 1111.at n=18A164437
• Number of zero-sum -n..n arrays of 4 elements with adjacent element differences also in -n..n.at n=20A202254
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 705", based on the 5-celled von Neumann neighborhood.at n=23A273419
• Triangle read by rows: T(n,k) is the number of chains in the poset of plane partitions ordered by inclusion that end with a plane partition of n and have length k.at n=24A389604