0,2

a(n)=A000096 + 6 * A001477, a(n)=A056119 + A001477 and a(n)=A056126 - A001477 - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Oct 01 2006

a(n) = A126890(n,7) for n>6. - Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Dec 30 2006

G.f.(x)=x(8-7x)/(1-x)^3.

a(n)=C(n,2)-7*n,n>=15 - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Nov 26 2006

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-1,8), for n>=1. [From Milan R. Janjic (agnus(AT)blic.net), Dec 20 2008]

a(n)=n+a(n-1)+6 (with a(1)=0) [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Nov 19 2009]

For n=2, a(2)=2+0+6=8; n=3, a(3)=3+8+6=17; n=4, a(4)=4+17+6=27 [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Nov 19 2009]

a:=n->sum(floor(k+2*n/(k+n)), k=7..n): seq(a(n), n=6..56); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Oct 01 2006

[seq(binomial(n, 2)-7*n, n=15..65)]; - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Nov 26 2006

seq(sum(k, k=8..n), n=7..57); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Mar 09 2008

a:=n->sum(numer (k/(k+3)), k=8..n): seq(a(n), n=7..57); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), May 31 2008

with(finance):seq(add(cashflows([2, k, 5], 0 ), k=1..n), n=0..50); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jun 22 2008

i=-7; 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]

Cf. A056119.

Cf. A000096, A056119, A056126, A056000, A001477.

Sequence in context: A017257 A052222 A044441 this_sequence A028884 A099358 A077222

Adjacent sequences: A056118 A056119 A056120 this_sequence A056122 A056123 A056124

easy,nonn,new

Barry E. Williams, Jul 06 2000

More terms from James A. Sellers (sellersj(AT)math.psu.edu), Jul 07 2000