180254domain: NAppears in sequencesMacMahon's solid partitions of n in which 3 is the smallest summand.at n=16A002044a(n) = Sum_{k=0..n} binomial(k, 6*(n-k)).at n=22A293169Number of compositions of 7*n-1 into parts 6 and 7.at n=18A373933a(n) = Sum_{k=0..floor(n/2)} binomial(k,3*(n-2*k)).at n=44A392253