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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A203010 (n-1)-st elementary symmetric function of first n Lucas numbers, starting with L(1)=1.

Original entry on oeis.org

1, 4, 19, 145, 1679, 31146, 919866, 43716030, 3345087696, 413168662224, 82432477483344, 26585428576089600, 13864587294260493504, 11694921751248976025856, 15957837208927564640940096, 35227081534568618432596098240
Offset: 1

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Author

Clark Kimberling, Dec 29 2011

Keywords

Comments

From R. J. Mathar, Oct 01 2016 (Start):
The k-th elementary symmetric functions of the A000204(j), j=1..n, form a triangle T(n,k), 0<=k<=n, n>=0:
1
1 1
1 4 3
1 8 19 12
1 15 75 145 84
1 26 240 970 1679 924
1 44 708 5290 19139 31146 16632
1 73 1984 25822 172549 586177 919866 482328
1 120 5415 119070 1386183 8695980 28470185 43716030 22669416
This here is the first subdiagonal. The diagonal is A070825. The 2nd column is A027961. (End)

Crossrefs

Cf. A203009.

Programs

  • Mathematica
    f[k_] := LucasL[k]; t[n_] := Table[f[k], {k, 1, n}]
    a[n_] := SymmetricPolynomial[n - 1, t[n]]
    Table[a[n], {n, 1, 16}] (* A203010 *)

A237498 Riordan array (1/(1-x-x^2), x/(1+2*x)).

Original entry on oeis.org

1, 1, 1, 2, -1, 1, 3, 4, -3, 1, 5, -5, 10, -5, 1, 8, 15, -25, 20, -7, 1, 13, -22, 65, -65, 34, -9, 1, 21, 57, -152, 195, -133, 52, -11, 1, 34, -93, 361, -542, 461, -237, 74, -13, 1, 55, 220, -815, 1445, -1464, 935, -385, 100, -15, 1, 89, -385, 1850, -3705
Offset: 0

Views

Author

Philippe Deléham, Feb 08 2014

Keywords

Comments

First column: Fibonacci numbers A000045(n+1).

Examples

			Triangle begins:
   1;
   1,    1;
   2,   -1,    1;
   3,    4,   -3,    1;
   5,   -5,   10,   -5,   1;
   8,   15,  -25,   20,  -7,   1;
  13,  -22,   65,  -65,  34,  -9,  1;
  ...
Production matrix is:
   1,  1;
   1, -2,  1;
   2,  0, -2,  1;
   4,  0,  0, -2,  1;
   8,  0,  0,  0, -2,  1;
  16,  0,  0,  0,  0, -2,  1;
  32,  0,  0,  0,  0,  0, -2,  1;
  64,  0,  0,  0,  0,  0,  0, -2,  1;
  ...
		

Crossrefs

Columns: A000045, A084179.

Programs

  • Mathematica
    nmax=10;Flatten[CoefficientList[Series[CoefficientList[Series[(1 + 2*x) / ((1 + 2*x - y*x) * (1 - x - x^2)), {x, 0, nmax }], x], {y, 0, nmax}], y]] (* Indranil Ghosh, Mar 15 2017 *)

Formula

Sum_{k=0..n} T(n,k)*x^k = A000045(n+1), A098600(n), A000032(n+1), A027961(n+1), A027974(n) for x = 0, 1, 2, 3, 4 respectively.
T(n,k) = T(n-1,k-1) - T(n-1,k) + 3*T(n-2,k) - T(n-2,k-1) + 2*T(n-3,k) - T(n-3,k-1), T(0,0) = T(1,0) = T(1,1) = T(2,2) = 1, T(2,0) = 2, T(2,1) = -1, T(n,k) = 0 if k<0 or if k>n.
T(n,0) = T(n-1,0) + T(n-2,0) with T(0,0) = T(1,0) = 1, T(n,k) = T(n-1,k-1) - 2*T(n-1,k) for k>=1.
G.f.: (1+2*x)/((1+2*x-y*x)*(1-x-x^2)).

A317360 Triangle a(n, k) read by rows: coefficient triangle that gives Lucas powers and sums of Lucas powers.

Original entry on oeis.org

1, 1, 2, 1, 7, -4, 1, 24, -23, -8, 1, 76, -164, -79, 16, 1, 235, -960, -1045, 255, 32, 1, 716, -5485, -11155, 5940, 831, -64, 1, 2166, -29816, -116480, 109960, 32778, -2687, -128, 1, 6527, -158252, -1143336, 2024920, 1029844, -176257, -8703, 256, 1, 19628, -822291, -10851888, 34850816, 32711632, -9230829, -937812, 28159, 512
Offset: 0

Views

Author

Tony Foster III, Jul 26 2018

Keywords

Examples

			n\k|  0  1      2       3        4       5         6        7      8     9
---+-------------------------------------------------------------------------
0  |  1
1  |  1  2
2  |  1  7     -4
3  |  1  24    -23     -8
4  |  1  76    -164    -79       16
5  |  1  235   -960    -1045     255     32
6  |  1  716   -5485   -11155    5940    831      -64
7  |  1  2166  -29816  -116480   109960  32778    -2687    -128
8  |  1  6527  -158252 -1143336  2024920 1029844  -176257  -8703   256
9  |  1  19628 -822291 -10851888 4850816 32711632 -9230829 -937812 28159 512
		

Crossrefs

Programs

  • PARI
    lucas(p)=2*fibonacci(p+1)-fibonacci(p);
    S(n, k) = (-1)^floor((k+1)/2)*(prod(j=0, k-1, fibonacci(n-j))/prod(j=1, k, fibonacci(j)));
    T(n, k) = sum(j=0, k, lucas(k+1-j)^n * S(n+1, j));
    tabl(m) = for (n=0, m, for (k=0, n, print1(T(n, k), ", ")); print);
    tabl(9);

Formula

a(n, k) = Sum_{j=0..k} Lucas(k+1-j)^n * A055870(n+1, j).
Sum_{j=0..n} a(n, n-j) * A010048(k-1+j, n) = Lucas(k)^n.
Sum_{j=0..n} a(n, n-j) * A305695(k-2+j, n-1) = Sum_{t=1..k} Lucas(t)^n.
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