90265domain: NAppears in sequencesNumber of free hexagonal polygons of symmetry class C_(2h) and area n.at n=17A121210Lengths of binary representations of prime Fibonacci numbers.at n=34A215367Number of partitions of (4, n) into a sum of distinct pairs.at n=32A268347a(1) = 1; a(n+1) = Sum_{d|n, n/d odd} a(d)^(n/d).at n=50A307780