42178domain: NAppears in sequencesNumber of tilings of a 4 X n rectangle using integer-sided rectangular tiles of area 4.at n=16A220123Coefficients in expansion of 1/(1 + 2*x - 3*x^3).at n=19A317499G.f. Sum_{n=-oo..+oo} x^n * (1 + x^n)^(n^3).at n=16A386669