%I A050929
%S A050929 1,2,11,47,198,713,2423,7388,21003,55433,137944,324659,729022,1567139,
%T A050929 3242954,6479759,12547894,23607614,43267994,77405064,135435666,
%U A050929 232137202,390371944,644897542,1047890293,1676518363,2643628813
%N A050929 Number of directed multigraphs with loops on 4 nodes with n arcs.
%F A050929 G.f.: (x^26-x^25 + 4*x^24 + 18*x^23 + 63*x^22 + 151*x^21 + 402*x^20 + 
               790*x^19 + 1511*x^18 + 2353*x^17 + 3400*x^16 + 4296*x^15 + 5115*x^14 
               + 5266*x^13 + 5115*x^12 + 4296*x^11 + 3400*x^10 + 2353*x^9 + 1511*x^8 
               + 790*x^7 + 402*x^6 + 151*x^5 + 63*x^4 + 18*x^3 + 4*x^2-x + 1)/((x^4-1)^4*(x^3-1)^5*(x^2-1)^4*(x-1)^3).
%Y A050929 Cf. A005993.
%Y A050929 Sequence in context: A142346 A106980 A089682 this_sequence A019005 A112288 
               A003442
%Y A050929 Adjacent sequences: A050926 A050927 A050928 this_sequence A050930 A050931 
               A050932
%K A050929 easy,nonn
%O A050929 0,2
%A A050929 Vladeta Jovovic (vladeta(AT)eunet.rs), Dec 30 1999