%I A133694
%S A133694 1,7,16,28,43,61,82,106,133,163,196,232,271,313,358,406,457,511,568,628,
%T A133694 691,757,826,898,973,1051,1132,1216,1303,1393,1486,1582,1681,1783,1888,
%U A133694 1996,2107,2221,2338,2458,2581,2707,2836,2968,3103,3241,3382,3526,3673
%N A133694 a(n) = 3*A000217(n) - 2.
%C A133694 Contribution from Gary W. Adamson (qntmpkt(AT)yahoo.com), May 01 2009: 
               (Start)
%C A133694 Equals (1, 2, 3, 4,...) convolved with (1, 5, 3, 3, 3,...). a(4) = 28 
               =
%C A133694 (1, 2, 3, 4) dot (3, 3, 5, 1) = (3 + 6 + 15 + 4). (End)
%F A133694 a(n) = 3*T(n) - 2, where T(n) = n-th Triangular number of A000217. A133694 
               = binomial transform of [1, 6, 3, 0, 0, 0,...].
%F A133694 Row sums of triangle A133981 - Gary W. Adamson (qntmpkt(AT)yahoo.com), 
               Sep 30 2007
%F A133694 a(n)=a(n-1)+3n (with a(1)=1) [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), 
               Oct 08 2009]
%e A133694 a(3) = 16 = 3*T(3) - 2 = 3*6 - 2.
%e A133694 a(4) = 28 = (1, 3, 3, 1) dot (1, 6, 3, 0) = (1, 18, 9, 0) = 28.
%e A133694 n=2, a(2)=1+6=7; n=3, a(3)=7+9=16; n=4, a(4)=16+12=28 [From Vincenzo 
               Librandi (vincenzo.librandi(AT)tin.it), Oct 08 2009]
%t A133694 s=1;lst={};Do[s+=n-3;If[s>0,AppendTo[lst,s]],{n,0,6!,3}];lst [From Vladmir 
               Orlovsky (4vladimir(AT)gmail.com), Nov 04 2008]
%Y A133694 Cf. A000217.
%Y A133694 Cf. A133981.
%Y A133694 Sequence in context: A052221 A119461 A028560 this_sequence A024627 A140511 
               A121470
%Y A133694 Adjacent sequences: A133691 A133692 A133693 this_sequence A133695 A133696 
               A133697
%K A133694 nonn
%O A133694 1,2
%A A133694 Gary W. Adamson (qntmpkt(AT)yahoo.com), Sep 20 2007
%E A133694 More terms and Mathematica program Vladmir Orlovsky (4vladimir(AT)gmail.com), 
               Nov 04 2008