cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A035039 a(n) = 2^n - C(n,0) - C(n,1) - ... - C(n,6).

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 0, 1, 9, 46, 176, 562, 1586, 4096, 9908, 22819, 50643, 109294, 230964, 480492, 988116, 2014992, 4084248, 8243109, 16587165, 33308926, 66794952, 133820134, 267936278, 536249296, 1072973612, 2146540999
Offset: 0

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Comments

Partial sums of A035038.

Crossrefs

Programs

  • Haskell
    a035039 n = a035039_list !! n
    a035039_list = map (sum . drop 7) a007318_tabl
    -- Reinhard Zumkeller, Jun 20 2015
  • Maple
    a:=n->sum(binomial(n,j),j=7..n): seq(a(n), n=0..31); # Zerinvary Lajos, Feb 12 2007
  • Mathematica
    a=1;lst={};s1=s2=s3=s4=s5=s6=s7=0;Do[s1+=a;s2+=s1;s3+=s2;s4+=s3;s5+=s4;s6+=s5;s7+=s6;AppendTo[lst,s7];a=a*2,{n,5!}];lst (* Vladimir Joseph Stephan Orlovsky, Jan 10 2009 *)
    Table[2^n-Total[Binomial[n,Range[0,6]]],{n,40}] (* or *) LinearRecurrence[ {9,-35,77,-105,91,-49,15,-2},{0,0,0,0,0,0,0,1},40] (* Harvey P. Dale, Apr 22 2016 *)

Formula

a(n) = A055248(n,7).
G.f.: x^7/((1-2*x)*(1-x)^7).
a(n) = Sum_{k=0..n}, C(n, k+7) = Sum_{k=7..n} C(n, k); a(n) = 2a(n-1) + C(n-1, 6). - Paul Barry, Aug 23 2004