%I A056126
%S A056126 0,9,19,30,42,55,69,84,100,117,135,154,174,195,217,240,264,289,315,342,
%T A056126 370,399,429,460,492,525,559,594,630,667,705,744,784,825,867,910,954,
%U A056126 999,1045,1092,1140,1189,1239,1290,1342,1395,1449,1504,1560,1617,1675
%N A056126 a(n)=n*(n+17)/2.
%C A056126 a(n)=A000096 + 7 * A001477, a(n)=A056121 + A001477 and a(n)=A051942 - 
               A001477 - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Oct 01 2006
%C A056126 a(n) = A126890(n,8) for n>7. - Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), 
               Dec 30 2006
%F A056126 G.f.(x)=x(9-8x)/(1-x)^3.
%F A056126 a(n)=C(n,2)-8*n,n>=17 - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), 
               Nov 26 2006
%F A056126 If we define f(n,i,a)=sum(binomial(n,k)*stirling1(n-k,i)*product(-a-j,
               j=0..k-1),k=0..n-i), then a(n) = -f(n,n-1,9), for n>=1. [From Milan 
               R. Janjic (agnus(AT)blic.net), Dec 20 2008]
%F A056126 a(n)=n+a(n-1)+7 (with a(1)=0) [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), 
               Nov 19 2009]
%e A056126 For n=2, a(2)=2+0+7=9; n=3, a(3)=3+9+7=19; n=4, a(4)=4+19+7=30 [From 
               Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Nov 19 2009]
%p A056126 a:=n->sum(floor(k+2*n/(k+n)), k=8..n): seq(a(n),n=7..57); - Zerinvary 
               Lajos (zerinvarylajos(AT)yahoo.com), Oct 01 2006
%p A056126 [seq(binomial(n,2)-8*n,n=17..67)]; - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), 
               Nov 26 2006
%p A056126 a:=n->sum(n, j=18..n): seq(a(n)/2, n=17..67); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), 
               Feb 17 2008
%p A056126 a:=n->sum(denom (k/(k+3)), k=6..n): seq(a(n), n=5..55); - Zerinvary Lajos 
               (zerinvarylajos(AT)yahoo.com), May 31 2008
%p A056126 with(finance):seq(add(cashflows([2,k,6], 0 ),k=1..n),n=0..50); - Zerinvary 
               Lajos (zerinvarylajos(AT)yahoo.com), Jun 22 2008
%t A056126 i=-8;s=0;lst={};Do[s+=n+i;If[s>=0, AppendTo[lst, s]], {n, 0, 6!, 1}];
               lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Oct 29 2008]
%Y A056126 Cf. A056121.
%Y A056126 Cf. A000096, A056121, A051942, A056000, A001477.
%Y A056126 Cf. A001477, A098849, A120071, A132760, A132761, A132765.
%Y A056126 Sequence in context: A043525 A031499 A017377 this_sequence A051811 A034056 
               A157034
%Y A056126 Adjacent sequences: A056123 A056124 A056125 this_sequence A056127 A056128 
               A056129
%K A056126 easy,nonn,new
%O A056126 0,2
%A A056126 Barry E. Williams, Jul 07 2000
%E A056126 More terms from James A. Sellers (sellersj(AT)math.psu.edu), Jul 10 2000