3344567domain: NAppears in sequencesNumber of binary words of length n in which the ones occur only in blocks of length at least 4.at n=37A005253Number of compositions of 5*n-4 into parts 2 and 5.at n=15A369844Expansion of (1 + x)^2/(1 - x^2*(1 + x)^3).at n=24A375317a(n) = Sum_{k=0..floor(2*n/5)} binomial(2*n-3*k,2*k).at n=19A391541