61084037575domain: NAppears in sequencesGaussian binomial coefficient [ n,2 ] for q = -2.at n=18A015249Exponential self-convolution of Jacobsthal numbers (divided by 2).at n=20A084152Jacobsthal oblong numbers.at n=19A084175Jac(n)(2Jac(n)-1).at n=19A095129