%I A140091
%S A140091 0,6,15,27,42,60,81,105,132,162,195,231,270,312,357,405,456,510,567,627,
%T A140091 690,756,825,897,972,1050,1131,1215,1302,1392,1485,1581,1680,1782,1887,
%U A140091 1995,2106,2220,2337,2457,2580,2706,2835,2967
%N A140091 3n(n+3)/2.
%F A140091 a(n) = A000096(n)*3 = (3*n^2 + 9*n)/2 = n(3n+9)/2.
%p A140091 with(finance):seq(add(cashflows([2,k,n], 0 ),k=2..n),n=1..45); - Zerinvary 
               Lajos (zerinvarylajos(AT)yahoo.com), Jun 22 2008
%t A140091 s=0;lst={};Do[s+=n+1;s+=n+2;s+=n+3;AppendTo[lst, s], {n, 0, 4!, 1}];lst 
               [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Oct 30 2008]
%t A140091 lst={};Do[AppendTo[lst, 3*n*(n+3)/2], {n, 0, 6!}];lst [From Vladimir 
               Orlovsky (4vladimir(AT)gmail.com), Nov 06 2008]
%t A140091 Table[Sum[i + n - 3, {i, 0, n}], {n, 2, 45}] [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), 
               Jul 11 2009]
%Y A140091 Cf. A000096, A000326, A005449, A045943, A115067, A140090, A059845, A140672, 
               A140673, A140674, A140675.
%Y A140091 The generalized pentagonal numbers b*n+3*n*(n-1)/2, for b = 1 through 
               12, form sequences A000326, A005449, A045943, A115067, A140090, A140091, 
               A059845, A140672, A140673, A140674, A140675, A151542.
%Y A140091 Sequence in context: A022601 A112150 A072257 this_sequence A165454 A063525 
               A161777
%Y A140091 Adjacent sequences: A140088 A140089 A140090 this_sequence A140092 A140093 
               A140094
%K A140091 easy,nonn
%O A140091 0,2
%A A140091 Omar E. Pol (info(AT)polprimos.com), May 22 2008