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 1-4 of 4 results.

A230160 Decimal expansion of the positive real solution of the equation x^k-x-1=0. Case k=7.

Original entry on oeis.org

1, 1, 1, 2, 7, 7, 5, 6, 8, 4, 2, 7, 8, 7, 0, 5, 4, 7, 0, 6, 2, 9, 7, 0, 4, 0, 2, 0, 5, 7, 1, 0, 9, 2, 9, 3, 5, 6, 0, 6, 8, 5, 9, 2, 7, 1, 8, 5, 5, 2, 8, 3, 6, 8, 1, 4, 8, 5, 7, 0, 1, 6, 2, 8, 0, 0, 7, 1, 6, 6, 3, 3, 2, 5, 7, 9, 5, 2, 8, 4, 4, 3, 4, 5, 9, 2, 7
Offset: 1

Views

Author

Paolo P. Lava, Oct 11 2013

Keywords

Comments

Also decimal expansion of (1+(1+(1+ ... )^(1/k))^(1/k))^(1/k), with k integer and k<0. Case k=7.

Examples

			1.1127756842787054706297040205710929356068592718552836814...
		

Crossrefs

Programs

  • Maple
    with(numtheory); P:=proc(q,h) local a,n; a:=(q+1)^(1/h);
    for n from q by -1 to 1 do a:=(1+a)^(1/h);od;
    print(evalf(a,1000)); end: P(1000,7);
  • Mathematica
    Root[x^7 - x - 1, 1] // RealDigits[#, 10, 100]& // First (* Jean-François Alcover, Feb 18 2014 *)

A230162 Decimal expansion of the positive real solution of the equation x^k-x-1=0. Case k=9.

Original entry on oeis.org

1, 0, 8, 5, 0, 7, 0, 2, 4, 5, 4, 9, 1, 4, 5, 0, 8, 2, 8, 3, 3, 6, 8, 9, 5, 8, 6, 4, 0, 9, 7, 3, 1, 4, 2, 3, 4, 0, 5, 0, 6, 5, 3, 6, 3, 1, 0, 3, 0, 8, 9, 6, 5, 8, 1, 4, 6, 8, 6, 1, 5, 5, 3, 3, 3, 6, 5, 1, 8, 0, 4, 9, 9, 4, 0, 1, 1, 5, 7, 1, 9, 9, 7, 4, 1, 9, 3
Offset: 1

Views

Author

Paolo P. Lava, Oct 11 2013

Keywords

Comments

Also decimal expansion of (1+(1+(1+ ... )^(1/k))^(1/k))^(1/k), with k integer and k<0. Case k=9.

Examples

			1.0850702454914508283368958640973142340506536310308965814...
		

Crossrefs

Programs

  • Maple
    with(numtheory); P:=proc(q,h) local a,n; a:=(q+1)^(1/h);
    for n from q by -1 to 1 do a:=(1+a)^(1/h);od;
    print(evalf(a,1000)); end: P(1000,9);
  • Mathematica
    Root[(#^9-#-1)&, 1] // RealDigits[#, 10, 100]& // First (* Jean-François Alcover, Feb 18 2014 *)
    RealDigits[x/.FindRoot[x^9-x-1==0,{x,1},WorkingPrecision->100]][[1]] (* Harvey P. Dale, Jul 31 2017 *)

A298814 Decimal expansion of the greatest real zero of x^8 - 2*x^4 - x + 1.

Original entry on oeis.org

1, 2, 0, 3, 3, 6, 8, 5, 3, 8, 1, 5, 0, 1, 5, 5, 0, 3, 4, 4, 5, 1, 0, 1, 8, 4, 7, 1, 9, 6, 5, 2, 9, 7, 0, 9, 4, 2, 3, 0, 4, 0, 9, 8, 8, 2, 7, 6, 3, 6, 5, 7, 3, 2, 7, 1, 8, 2, 9, 5, 8, 2, 0, 0, 1, 5, 8, 2, 9, 2, 3, 7, 4, 2, 0, 7, 7, 4, 3, 0, 0, 9, 5, 1, 4, 9
Offset: 1

Views

Author

Clark Kimberling, Feb 13 2018

Keywords

Comments

Let (d(n)) = (0,0,1,0,0,1,...), s(n) = (s(n-1) + d(n))^(1/2) for n > 0, and s(0) = 1.
Then s(3n) -> 1.096981557798..., as in A230161;
s(3n+1) -> 1.2033685381501..., as in A298814;
s(3n+2) -> 1.44809583860..., as in A298815.

Examples

			Greatest real zero = 1.2033685381501...
		

Crossrefs

Programs

  • Mathematica
    r = x /. NSolve[x^8 - 2 x^4 - x + 1 == 0, x, 10000][[8]];
    RealDigits[r][[1]]; (* A298814 *)
  • PARI
    solve(x=1, 2, x^8 - 2*x^4 - x + 1) \\ Michel Marcus, Nov 05 2018

A298815 Decimal expansion of the greatest real zero of x^8 - 4*x^6 + 6*x^4 - 4*x^2 - x + 1.

Original entry on oeis.org

1, 4, 4, 8, 0, 9, 5, 8, 3, 8, 6, 0, 9, 6, 4, 1, 1, 3, 2, 5, 8, 3, 8, 6, 9, 9, 9, 6, 8, 1, 0, 7, 3, 3, 6, 4, 6, 2, 2, 7, 9, 6, 5, 2, 7, 7, 5, 8, 6, 5, 5, 5, 7, 1, 5, 1, 8, 3, 7, 9, 7, 3, 4, 9, 7, 1, 8, 5, 8, 4, 5, 3, 2, 1, 0, 6, 9, 1, 1, 6, 3, 7, 8, 8, 4, 3
Offset: 1

Views

Author

Clark Kimberling, Feb 13 2018

Keywords

Comments

Let (d(n)) = (0,0,1,0,0,1,...), s(n) = (s(n-1) + d(n))^(1/2) for n > 0, and s(0) = 1.
Then s(3n) -> 1.096981557798... , as in A230161;
s(3n+1) -> 1.2033685381501..., as in A298814;
s(3n+2) -> 1.44809583860..., as in A298815.

Examples

			greatest real zero = 1.4480958386096...
		

Crossrefs

Programs

  • Mathematica
    r = x /. NSolve[x^8 - 4 x^6 + 6 x^4 - 4 x^2 - x  + 1 == 0, x, 10000][[8]];
    RealDigits[r][[1]]; (* A298815 *)
Showing 1-4 of 4 results.