67681

Appears in sequences

• Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted the two central terms are both 57.at n=4A031645
• Number of nonempty subsets of {1, 2, ..., n} with <=8 pairwise coprime elements.at n=32A187269
• First differences of A000219.at n=21A191659
• Number of n-bead necklaces labeled with numbers -7..7 not allowing reversal, with sum zero and avoiding the patterns z z+1 z+2 and z z-1 z-2.at n=5A209114
• Number of 6-bead necklaces labeled with numbers -n..n not allowing reversal, with sum zero and avoiding the patterns z z+1 z+2 and z z-1 z-2.at n=6A209118
• Number of twice-partitions of n with no repeated partitions.at n=18A296122
• Number of normal patterns matched by compositions of n.at n=12A335456