Search: id:A119851 Results 1-1 of 1 results found. %I A119851 %S A119851 1,3,9,26,1,75,6,216,27,622,106,1,1791,387,9,5157,1350,54,14849,4566, %T A119851 267,1,42756,15102,1179,12,123111,49113,4833,90,354484,157622,18798,536, %U A119851 1,1020696,500520,70317,2775,15,2938977,1575558,255231,13068,135 %N A119851 Triangle read by rows: T(n,k) is the number of ternary words of length n containing k 012's (n>=0, 0<=k<=floor(n/3)). %C A119851 Row n has 1+floor(n/3) terms. Sum of entries in row n is 3^n (A000244). T(n,0)=A076264(n). T(n,1)=A119852(n). Sum(k*T(n,k),k>=0)=(n-2)*3^(n-3)=A027741(n-1). %F A119851 G.f.=G(t,z)=1/(1-3z+z^3-tz^3). Recurrence relation: T(n,k)=3*T(n-1,k)-T(n-3, k)+T(n-3,k-1) for n>=3. %e A119851 T(4,1)=6 because we have 0012, 0120, 0121, 0122, 1012 and 2012. %e A119851 Triangle starts: %e A119851 1; %e A119851 3; %e A119851 9; %e A119851 26,1; %e A119851 75,6; %e A119851 216,27; %e A119851 622,106,1; %p A119851 G:=1/(1-3*z+z^3-t*z^3): Gser:=simplify(series(G,z=0,20)): P[0]:=1: for n from 1 to 15 do P[n]:=sort(coeff(Gser,z^n)) od: for n from 0 to 15 do seq(coeff(P[n],t,j),j=0..floor(n/3)) od; # yields sequence in triangular form %Y A119851 Cf. A000244, A076264, A119852, A027741. %Y A119851 Sequence in context: A074440 A006204 A013572 this_sequence A119825 A037260 A035313 %Y A119851 Adjacent sequences: A119848 A119849 A119850 this_sequence A119852 A119853 A119854 %K A119851 nonn,tabf %O A119851 0,2 %A A119851 Emeric Deutsch (deutsch(AT)duke.poly.edu), May 26 2006 Search completed in 0.001 seconds