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.

A152575 A triangle of coefficients of polynomials with roots as the Pi-digits base ten A000796(n)=d(n):d(1)=3; p(x,n)=-d(1)*Product[x-d(m),{m,2,n}].

Original entry on oeis.org

-3, 3, -3, -12, 15, -3, 12, -27, 18, -3, -60, 147, -117, 33, -3, 540, -1383, 1200, -414, 60, -3, -1080, 3306, -3783, 2028, -534, 66, -3, 6480, -20916, 26004, -15951, 5232, -930, 84, -3, -32400, 111060, -150936, 105759, -42111, 9882, -1350, 99, -3, 97200
Offset: 1

Views

Author

Roger L. Bagula, Dec 08 2008

Keywords

Comments

p(x,n)=Product[(x-i)^a(i),{i,0,9}]: a(i) is the count number of the
way the digits occur by the n-th digit.
The limiting polynomial is:
pL(x)=Product[(x-i),{i,0,9}]=
-362880 x + 1026576 x^2 - 1172700 x^3 + 723680 x^4 - 269325 x^5 + 63273 x^6 - 9450 x^7 + 870 x^8 - 45 x^9 + x^10;
since if the digits occur equally:
p(x,Infinity)=-3*Product[(x-i),{i,0,9}]^(Infinity/10).
Or at the n-th digits equality:
p(x,n)=-3*Product[(x-i),{i,0,9}]^(n/10).
The n+1 digit:
p(x,n+1)=p(x,n)*(x-d(n+1)).

Examples

			{-3},
{3, -3},
{-12,15, -3},
{12, -27, 18, -3},
{-60, 147, -117, 33, -3},
{540, -1383, 1200, -414, 60, -3},
{-1080, 3306, -3783, 2028, -534, 66, -3},
{6480, -20916, 26004, -15951, 5232, -930, 84, -3},
{-32400, 111060, -150936, 105759, -42111, 9882, -1350, 99, -3},
{97200, -365580, 563868, -468213, 232092, -71757, 13932, -1647, 108, -3}
		

Crossrefs

Programs

  • Mathematica
    Clear[a, p, n, m];
    a = Delete[Flatten[RealDigits[Pi, 10, 100]], 100];
    p[x_, n_] := If[n == 1, -a[[1]], -a[[1]]*Product[x - a[[m]], {m, 2, n}]];
    Table[CoefficientList[p[x, n], x], {n, 1, 10}]
    Flatten[%]

Formula

Pi-digits base ten A000796(n)=d(n):
p(x,n)=-d(1)*Product[x-d(m),{m,2,n}].