368734domain: NAppears in sequencesa(n) = Sum_{k=0..n} binomial(k, 6*(n-k)).at n=23A293169Number of compositions of 7*n-2 into parts 6 and 7.at n=19A373934a(n) = Sum_{k=0..floor(n/2)} binomial(k,3*(n-2*k)).at n=46A392253