A108669 - OEIS

%I #13 Jul 14 2019 12:38:05

%S 20,34,59,48,84,120,62,109,156,203,76,134,192,250,308,90,159,228,297,

%T 366,435,104,184,264,344,424,504,584,118,209,300,391,482,573,664,755,

%U 132,234,336,438,540,642,744,846,948,146,259,372,485,598,711,824,937

%N Triangle read by rows: T(n,k) = 11*k*n + 14*(n+k) + 20 (0 <= k <= n).

%C Kekulé numbers for certain benzenoids.

%D S. J. Cyvin and I. Gutman, Kekulé structures in benzenoid hydrocarbons, Lecture Notes in Chemistry, No. 46, Springer, New York, 1988 (p. 102).

%F G.f.: (20 - 6*z - t*z - 16*t*z^2 + 3*t^2*z^2)/((1-z)^2*(1-t*z)^3).

%e Triangle begins:

%e 20;

%e 34,59;

%e 48,84,120;

%e 62,109,156,203;

%p T:=proc(n,k) if k<=n then 11*k*n+14*(n+k)+20 else 0 fi end: for n from 0 to 10 do seq(T(n,k),k=0..n) od; # yields sequence in triangular form

%t Table[11*k*n+14(n+k)+20,{n,0,10},{k,0,n}]//Flatten (* _Harvey P. Dale_, Jul 14 2019 *)

%K nonn,tabl

%O 0,1

%A _Emeric Deutsch_, Jun 14 2005