109334domain: NAppears in sequencesNumbers n such that 237*2^n-1 is prime.at n=44A050877Number of n X n circulant singular (0,1) matrices over the reals.at n=20A086328Number of n X n (-1,1)-circulant matrices with determinant 0.at n=21A144926a(n) is the number of acyclic orientations of the edges of the n-prism.at n=3A338153