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.

A132039 E.g.f.: A(x) = Sum_{n>=0} a(n)*x^n/n! = exp( Sum_{n>=0} a(n)*x^(n+1)/(n+1) ) with a(0) = 1.

Original entry on oeis.org

1, 1, 2, 8, 74, 2122, 267292, 194323504, 980945301116, 39560543100700028, 14356125485861852659544, 52095666080476161483596777824, 2079492908949143825845786572097662328, 996080457608702027557335524810508733871848312
Offset: 0

Views

Author

Paul D. Hanna, Aug 07 2007

Keywords

Comments

Shifts A132039(n-1), n >= 1, one place left under MNL transform, see A274760. Pointed out by Paul D. Hanna. - Johannes W. Meijer, Aug 03 2016

Examples

			E.g.f.: A(x) = 1 + 1*x + 2*x^2/2! + 8*x^3/3! + 74*x^4/4! + 2122*x^5/5! +...;
E.g.f.: A(x) = exp(x + 1*x^2/2 + 2*x^3/3 + 8*x^4/4 + 74*x^5/5 + 2122*x^6/6 +...) .
		

Crossrefs

Programs

  • Maple
    A132039 := proc(n) option remember: if n=0 then 1 else add((n-1)!/k!*A132039(k)*A132039(n-1-k),k=0..n-1) fi: end: seq(A132039(n), n=0..13);
    nmax:=13: t1 := add(a(n)*x^n/n!, n=0..nmax): t2 := series(exp(add(a(n)*x^(n+1)/(n+1), n=0..nmax)), x, nmax+1): a(0) := 1: for n from 1 to nmax do a(n) := n!*coeff(t2, x, n) od: A132039 := proc(n): a(n) end: seq(A132039(n), n=0..nmax); # Johannes W. Meijer, Aug 03 2016
  • PARI
    {a(n)=if(n==0,1,n!*polcoeff(exp(sum(k=0,n-1,a(k)*x^(k+1)/(k+1))+x^2*O(x^n)),n))}

Formula

a(n+1) = Sum_{k=0..n} n!/k!*a(k)*a(n-k). - Vladeta Jovovic, Jul 08 2008

A275593 Shifts 2 places left under MNL transform.

Original entry on oeis.org

1, 1, 1, 2, 6, 30, 270, 5100, 229380, 27535260, 9496469340, 10086965678520, 34571745136244520, 403054252638271664040, 16565160940382442188713320, 2510059126960200448967150682000, 1444160075122431073529236697462766000
Offset: 1

Views

Author

Johannes W. Meijer, Aug 03 2016

Keywords

Comments

Shifts two places left under MNL transform, see A274760.
The Maple program is based on a program by Alois P. Heinz, see A007548 and A274804.

Crossrefs

Programs

  • Maple
    mnltr:= proc(p) local g; g:= proc(n) option remember; `if` (n=0, 1, add(((n-1)!/(n-k)!)*p(k) *g(n-k), k=1..n)): end: end: d := mnltr(c): c := n->`if`(n<=2, 1, d(n-2)): A275593 := n -> c(n): seq(A275593(n), n=1..16);
  • Mathematica
    mnltr[p_] := Module[{g}, g[n_] := g[n] = If[n == 0, 1, Sum[((n-1)!/(n-k)!)* p[k]*g[n-k], {k, 1, n}]]; g]; d = mnltr[a]; a[n_] := If[n <= 2, 1, d[n-2] ]; Array[a, 17] (* Jean-François Alcover, Nov 07 2017, translated from Maple *)

A275594 Shifts 3 places left under MNL transform.

Original entry on oeis.org

1, 1, 1, 1, 2, 6, 24, 144, 1464, 26808, 935184, 67404816, 10401844896, 3508019017056, 2732681228689152, 5018025242941566336, 21914759744001662937984, 238559201308551667344338304, 6565759935393013059564090526464
Offset: 1

Views

Author

Johannes W. Meijer, Aug 03 2016

Keywords

Comments

Shifts three places left under MNL transform, see A274760.
The Maple program is based on a program by Alois P. Heinz, see A007548 and A274804.

Crossrefs

Programs

  • Maple
    mnltr:= proc(p) local g; g:= proc(n) option remember; `if` (n=0, 1, add(((n-1)!/(n-k)!)*p(k) *g(n-k), k=1..n)): end: end: d := mnltr(c): c := n->`if`(n<=3, 1, d(n-3)): A275594 := n-> c(n): seq(A275594(n), n=1..19);
  • Mathematica
    mnltr[p_] := Module[{g}, g[n_] := g[n] = If [n == 0, 1, Sum[((n-1)!/(n-k)!) *p[k]*g[n-k], {k, 1 n}]]; g]; d = mnltr[c]; c [n_] := If[n <= 3, 1, d[n - 3]]; A275594[n_] := c[n]; Table[A275594[n], {n, 1, 19}] (* Jean-François Alcover, Jul 22 2017, translated from Maple *)
Showing 1-3 of 3 results.