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.

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A276997 Denominators of coefficients of polynomials arising from applying the complete Bell polynomials to k!B_k(x)/(k*(k-1)) with B_k(x) the Bernoulli polynomials.

Original entry on oeis.org

1, 1, 1, 6, 1, 1, 1, 2, 2, 1, 60, 1, 1, 1, 1, 1, 6, 2, 3, 1, 1, 504, 4, 4, 1, 1, 1, 1, 1, 24, 8, 12, 2, 2, 2, 1, 2160, 18, 9, 3, 2, 1, 3, 1, 1, 1, 60, 4, 6, 1, 5, 1, 1, 1, 1, 3168, 48, 16, 6, 3, 2, 2, 1, 2, 1, 1, 1, 288, 32, 144, 12, 12, 4, 2, 1, 6, 2, 1
Offset: 0

Views

Author

Peter Luschny, Oct 01 2016

Keywords

Comments

For formulas and references see A276996.
Compare T(n,0) with A220411.

Examples

			Triangle starts:
     1;
     1,  1;
     6,  1,  1;
     1,  2,  2,  1;
    60,  1,  1,  1, 1;
     1,  6,  2,  3, 1, 1;
   504,  4,  4,  1, 1, 1, 1;
     1, 24,  8, 12, 2, 2, 2, 1;
  2160, 18,  9,  3, 2, 1, 3, 1, 1;
		

Crossrefs

Cf. A276996 (numerators), A220411.

Programs

  • Maple
    A276997_row := proc(n) local p;
    p := (n,x) -> CompleteBellB(n,0,seq((k-2)!*bernoulli(k,x),k=2..n)):
    seq(denom(coeff(p(n,x),x,k)), k=0..n) end:
    seq(A276997_row(n), n=0..11);
  • Mathematica
    CompleteBellB[n_, zz_] := Sum[BellY[n, k, zz[[1 ;; n-k+1]]], {k, 1, n}];
    p[n_, x_] := CompleteBellB[n, Join[{0}, Table[(k-2)! BernoulliB[k, x], {k, 2, n}]]];
    row[0] = {1}; row[1] = {1, 1}; row[n_] := CoefficientList[p[n, x], x] // Denominator;
    Table[row[n], {n, 0, 11}] // Flatten (* Jean-François Alcover, Sep 09 2018 *)

A276998 Coefficients of polynomials arising from applying the complete Bell polynomials to k!B_k(x) where B_k(x) are the Bernoulli polynomials.

Original entry on oeis.org

1, 1, 2, 1, 12, 6, -1, 72, 24, -24, 1, 1440, 120, -960, 200, 37, 43200, -9360, -44280, 20640, 3750, -1493, 1814400, -997920, -2484720, 2028600, 271740, -378966, 14017, 25401600, -23042880, -42497280, 54159840, 3328080, -18236064, 1977248, 751267
Offset: 0

Views

Author

Peter Luschny, Oct 03 2016

Keywords

Examples

			Sequence of rational polynomials P_n(x) starts:
1;
1;
(2*x + 1)/2;
(12*x^2 + 6*x - 1)/6;
(72*x^3 + 24*x^2 - 24*x + 1)/12;
(1440*x^4 + 120*x^3 - 960*x^2 + 200*x + 37)/60;
(43200*x^5 - 9360*x^4 - 44280*x^3 + 20640*x^2 + 3750*x - 1493)/360;
Triangle starts:
[1]
[1]
[2, 1]
[12, 6, -1]
[72, 24, -24, 1]
[1440, 120, -960, 200, 37]
[43200, -9360, -44280, 20640, 3750, -1493]
		

Crossrefs

T(n,0) = A277174(n)/n for n>=1.

Programs

  • Maple
    P := proc(n) local B;
    B := (n, x) -> CompleteBellB(n, seq(k!*bernoulli(k, x), k=0..n)):
    sort(A048803(n)*B(n, x)) end:
    A276998_row := n -> PolynomialTools[CoefficientList](P(n), x, termorder=reverse):
    seq(op(A276998_row(n)), n=0..8);
    # Recurrence for the rational polynomials:
    A276998_poly := proc(n,x) option remember; local z; if n = 0 then return 1 fi;
    z := proc(k) option remember; k!*bernoulli(k,x) end;
    expand(add(binomial(n-1,j)*z(n-j-1)*A276998_poly(j,x),j=0..n-1)) end:
    for n from 0 to 5 do sort(A276998_poly(n,x)) od;
  • Mathematica
    (* b = A048803 *) b[0] = 1; b[n_] := b[n] = b[n-1] First @ Select[ Reverse @ Divisors[n], SquareFreeQ, 1];
    CompleteBellB[n_, zz_] := Sum[BellY[n, k, zz[[1 ;; n-k+1]]], {k, 1, n}];
    B[n_, x_] := CompleteBellB[n, Table[k!*BernoulliB[k, x], {k, 0, n}]];
    P[n_] := b[n] B[n, x];
    row[0] = {1}; row[n_] := CoefficientList[P[n], x] // Reverse;
    Table[row[n], {n, 0, 8}] // Flatten (* Jean-François Alcover, Sep 09 2018 *)

Formula

P_n(x) = Y_n(x_0, x_1, x_2,..., x_n), the complete Bell polynomials evaluated at x_k = k!*B_k(x) and B_k(x) the Bernoulli polynomials.
T(n,k) = A048803(n)*[x^k] P_n(x).
Showing 1-2 of 2 results.