%I A073974
%S A073974 0,1,9,54,210,1008,6300,40824,262440,1679616
%N A073974 Number of strings of length n over Z_6 with trace 0 and subtrace 3.
%H A073974 F. Ruskey <a href="http://www.theory.csc.uvic.ca/~cos/inf/trs/str/Zq/
               str_tr_subtr_Z6.html">Number of strings over Z_6 of given trace and 
               subtrace</a>
%F A073974 a(n; t, s) = a(n-1; t, s) + a(n-1; t+5, s+5t+1) + a(n-1; t+4, s+4t+4) 
               + a(n-1; t+3, s+3t+3) + a(n-1; t+2, s+2t+2) + a(n-1; t+1, s+t+1) 
               where t is the trace and s is the subtrace.
%Y A073974 Cf. A073971, A073972, A073973, A073975, A073976, A073977, A073978, A073979, 
               A073980, A073981, A073982, A073983, A073984, A073985, A073986, A073987, 
               A073988, A073989, A073990, A073991, A073992, A073993, A073994.
%Y A073974 Sequence in context: A152994 A034719 A013567 this_sequence A035927 A059597 
               A023008
%Y A073974 Adjacent sequences: A073971 A073972 A073973 this_sequence A073975 A073976 
               A073977
%K A073974 easy,nonn
%O A073974 1,3
%A A073974 Frank Ruskey, Nate Kube (fruskey(AT)cs.uvic.ca), Aug 16 2002