5477917domain: NAppears in sequencesa(n) = Sum_{k=0..n} C(n-k,3k).at n=28A003522Number of compositions of n such that two adjacent parts are not equal modulo 2.at n=40A062200Quadrisection of a generalized Padovan sequence.at n=21A099099a(n) = Sum_{k=0..floor(n/2)} binomial(2*n-k,3*k).at n=14A392400