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.

Showing 1-3 of 3 results.

A152688 Partial products of A152687.

Original entry on oeis.org

1, 1, 2, 48, 414720, 309586821120000, 62298599877271470735360000000000, 221419738218975714643056286355472083897548800000000000000000000, 30963454718960054822969246779894642673092903344400531870724683866888280945459200000000000000000000000000000000000
Offset: 1

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Keywords

Crossrefs

Programs

  • Mathematica
    lst={};p0=p1=p2=p3=1;Do[p0*=a[n];p1*=p0;p2*=p1;p3*=p2;AppendTo[lst,p3],{n,1,2*3!}];lst

Extensions

Better definition from Omar E. Pol, Aug 06 2009

A152689 Apply partial sum operator thrice to factorials.

Original entry on oeis.org

0, 0, 0, 1, 4, 11, 28, 79, 284, 1363, 8356, 61583, 523924, 5024179, 53479148, 624890431, 7946278828, 109195935539, 1612048228564, 25439293045903, 427278358483556, 7609502950269523, 143217213477235804, 2840152418116022399
Offset: 0

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Crossrefs

Programs

  • Magma
    [0] cat [((n^2 -3*n +1)*(&+[Factorial(k): k in [0..(n-1)]]) -(n-2)*Factorial(n) +2*(n-1))/2: n in [1..30]]; // G. C. Greubel, Sep 13 2018
  • Mathematica
    With S[n_]:= Sum[k!, {k,0,n-1}];
    Table[Sum[Sum[S[j], {j,0,m-1}], {m,0,n -1}], {n, 0, 30}] (* or *) Table[((n^2 - 3*n + 1)*S[n] - (n - 2)*n! + 2*(n - 1))/2, {n, 0, 30}] (* G. C. Greubel, Sep 13 2018 *)
  • PARI
    for(n=0,30, print1(((n^2-3*n+1)*sum(k=0,n-1, k!) - (n-2)*n! + 2*(n -1))/2, ", ")) \\ G. C. Greubel, Sep 13 2018
    

Formula

From G. C. Greubel, Sep 13 2018: (Start)
a(n) = Sum_{j=0..(n-1)} Sum_{m=0..(j-1)} !m, where !n = Sum_{k=0..(n-1)} k! = A003422(n).
a(n) = ((n^2 -3*n +1) * !n - (n-2)*n! + 2*(n-1))/2.
a(n) = Sum_{j=0..(n-1)} ((j-1) * !j - j! + 1) = Sum_{j=0..(n-1)} A014144(n). (End)

Extensions

Prepended zeros and changed offset by G. C. Greubel, Sep 13 2018

A152690 Partial sums of superfactorials (A000178).

Original entry on oeis.org

1, 2, 4, 16, 304, 34864, 24918064, 125436246064, 5056710181206064, 1834938528961266006064, 6658608419043265483506006064, 265790273955000365854215115506006064
Offset: 1

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Author

Keywords

Crossrefs

Programs

  • Mathematica
    lst={};p0=1;s0=0;Do[p0*=a[n];s0+=p0;AppendTo[lst,s0],{n,0,4!}];lst
    s = 0; lst = {s}; Do[s += BarnesG[n]; AppendTo[lst, s], {n, 2, 13, 1}]; lst (* Zerinvary Lajos, Jul 16 2009 *)
    Table[Sum[BarnesG[k+1],{k,1,n}],{n,1,15}] (* Vaclav Kotesovec, Jul 10 2015 *)

Formula

G.f.: W(0)/(2-2*x) , where W(k) = 1 + 1/( 1 - x*(k+1)!/( x*(k+1)! + 1/W(k+1) )); (continued fraction). - Sergei N. Gladkovskii, Aug 19 2013
a(n) ~ exp(1/12 - 3*n^2/4) * n^(n^2/2 - 1/12) * (2*Pi)^(n/2) / A, where A = A074962 = 1.2824271291... is the Glaisher-Kinkelin constant. - Vaclav Kotesovec, Jul 10 2015
a(n) = n! * G(n+1) + a(n-1), where G(z) is the Barnes G-function. - Daniel Suteu, Jul 23 2016
Showing 1-3 of 3 results.