%I A140674
%S A140674 0,10,23,39,58,80,105,133,164,198,235,275,318,364,413,465,520,578,639,
%T A140674 703,770,840,913,989,1068,1150,1235,1323,1414,1508,1605,1705,1808,1914,
%U A140674 2023,2135,2250,2368,2489,2613,2740,2870,3003,3139
%N A140674 n(3n+17)/2.
%F A140674 a(n)=(3*n^2 + 17*n)/2.
%F A140674 a(n) = 7*n + 3*A000217(n). - Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), 
               May 28 2008
%F A140674 a(n)=3*n+a(n-1)+4 (with a(1)=0) [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), 
               Nov 08 2009]
%e A140674 For n=2, a(2)=3*2+0+4=10; n=3, a(3)=3*3+10+4=23; a(4)=3*4+23+4=39 [From 
               Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Nov 08 2009]
%p A140674 with(finance):seq(add(cashflows([2,k,n], 0 ),k=4..n),n=3..46); - Zerinvary 
               Lajos (zerinvarylajos(AT)yahoo.com), Jun 22 2008
%t A140674 s=0;lst={s};Do[s+=n++ +10;AppendTo[lst, s], {n, 0, 7!, 3}];lst [From 
               Vladimir Orlovsky (4vladimir(AT)gmail.com), Nov 17 2008]
%Y A140674 Cf. A000326, A005449, A045943, A115067, A140090, A140091, A059845, A140672, 
               A140673, A140675.
%Y A140674 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 A140674 Sequence in context: A054095 A125618 A154033 this_sequence A072245 A135277 
               A156202
%Y A140674 Adjacent sequences: A140671 A140672 A140673 this_sequence A140675 A140676 
               A140677
%K A140674 easy,nonn
%O A140674 0,2
%A A140674 Omar E. Pol (info(AT)polprimos.com), May 22 2008