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 1-6 of 6 results.

A225002 Duplicate of A047290.

Original entry on oeis.org

1, 4, 6, 8, 11, 13, 15, 18, 20, 22, 25, 27, 29, 32, 34, 36, 39, 41, 43, 46, 48, 50, 53, 55, 57, 60, 62, 64, 67, 69, 71, 74, 76, 78, 81, 83, 85, 88, 90, 92, 95, 97, 99, 102, 104, 106, 109, 111, 113, 116, 118, 120, 123, 125, 127, 130, 132, 134, 137, 139, 141
Offset: 1

Views

Author

T. D. Noe, Apr 26 2013

Keywords

Programs

  • Mathematica
    th = E^(3/7); t = Table[Floor[1/FractionalPart[th^(1/n)]], {n, 100}]

A224996 a(n) = floor(1/f(x^(1/n))) for x = 2, where f computes the fractional part.

Original entry on oeis.org

2, 3, 5, 6, 8, 9, 11, 12, 13, 15, 16, 18, 19, 21, 22, 24, 25, 26, 28, 29, 31, 32, 34, 35, 37, 38, 39, 41, 42, 44, 45, 47, 48, 49, 51, 52, 54, 55, 57, 58, 60, 61, 62, 64, 65, 67, 68, 70, 71, 73, 74, 75, 77, 78, 80, 81, 83, 84, 86, 87, 88, 90, 91, 93, 94, 96, 97
Offset: 2

Views

Author

T. D. Noe, Apr 26 2013

Keywords

Comments

First denominator of continued fraction representing 2^(1/n): [1,a(n),....] so that 1+1/a(n) is first convergent for 2^(1/n). - Carmine Suriano, Apr 29 2014
a(n) is the largest integer y that satisfies (y+1)^n - y^n >= y^n, or equivalently (y+1)^n >= 2*y^n. - Charles Kusniec, Jan 19 2025

Crossrefs

Cf. A078607 (the smallest integer y that satisfies (y+1)^n - y^n < y^n).

Programs

  • Mathematica
    th = 2; t = Table[Floor[1/FractionalPart[th^(1/n)]], {n, 2, 100}]

Formula

a(n) = floor(n/log(2)-1/2). - Andrey Zabolotskiy, Dec 01 2017

A224995 Floor(1/f(x^(1/n))) for x = 3/2, where f computes the fractional part.

Original entry on oeis.org

2, 4, 6, 9, 11, 14, 16, 19, 21, 24, 26, 29, 31, 34, 36, 38, 41, 43, 46, 48, 51, 53, 56, 58, 61, 63, 66, 68, 71, 73, 75, 78, 80, 83, 85, 88, 90, 93, 95, 98, 100, 103, 105, 108, 110, 112, 115, 117, 120, 122, 125, 127, 130, 132, 135, 137, 140, 142, 145, 147, 149
Offset: 1

Views

Author

T. D. Noe, Apr 26 2013

Keywords

Crossrefs

Programs

  • Mathematica
    th = 3/2; t = Table[Floor[1/FractionalPart[th^(1/n)]], {n, 100}]

Formula

a(n) = floor(n/log(3/2)-1/2) for n>1. - Andrey Zabolotskiy, Dec 01 2017

A224997 Floor(1/f(x^(1/n))) for x = 17, where f computes the fractional part.

Original entry on oeis.org

8, 1, 32, 1, 1, 2, 2, 2, 3, 3, 3, 4, 4, 4, 5, 5, 5, 6, 6, 6, 7, 7, 7, 8, 8, 9, 9, 9, 10, 10, 10, 11, 11, 11, 12, 12, 12, 13, 13, 13, 14, 14, 15, 15, 15, 16, 16, 16, 17, 17, 17, 18, 18, 18, 19, 19, 19, 20, 20, 21, 21, 21, 22, 22, 22, 23, 23, 23, 24, 24, 24, 25
Offset: 2

Views

Author

T. D. Noe, Apr 26 2013

Keywords

Crossrefs

Programs

  • Mathematica
    th = 17; t = Table[Floor[1/FractionalPart[th^(1/n)]], {n, 2, 100}]

Formula

a(n) = floor(n/log(17)-1/2) for n>7. - Andrey Zabolotskiy, Dec 01 2017

A224998 Floor(1/f(x^(1/n))) for x = Pi, where f computes the fractional part.

Original entry on oeis.org

7, 1, 2, 3, 3, 4, 5, 6, 7, 8, 9, 9, 10, 11, 12, 13, 14, 15, 16, 16, 17, 18, 19, 20, 21, 22, 23, 23, 24, 25, 26, 27, 28, 29, 30, 30, 31, 32, 33, 34, 35, 36, 37, 37, 38, 39, 40, 41, 42, 43, 44, 44, 45, 46, 47, 48, 49, 50, 51, 51, 52, 53, 54, 55, 56, 57, 58, 58
Offset: 1

Views

Author

T. D. Noe, Apr 26 2013

Keywords

Crossrefs

Programs

  • Mathematica
    th = Pi; t = Table[Floor[1/FractionalPart[th^(1/n)]], {n, 100}]

Formula

a(n) = floor(n/log(Pi)-1/2) for n>4. - Andrey Zabolotskiy, Dec 01 2017

A220753 Expansion of (1+4*x+5*x^2-x^3)/((1-x)*(1+x)*(1-2*x^2)).

Original entry on oeis.org

1, 4, 8, 11, 22, 25, 50, 53, 106, 109, 218, 221, 442, 445, 890, 893, 1786, 1789, 3578, 3581, 7162, 7165, 14330, 14333, 28666, 28669, 57338, 57341, 114682, 114685, 229370, 229373, 458746, 458749, 917498, 917501, 1835002, 1835005, 3670010, 3670013
Offset: 0

Views

Author

Philippe Deléham, Apr 13 2013

Keywords

Crossrefs

Programs

  • Magma
    m:=41; R:=PowerSeriesRing(Integers(), m); Coefficients(R!((1+4*x+5*x^2-x^3)/((1-x)*(1+x)*(1-2*x^2)))); // Bruno Berselli, Apr 13 2013
  • Mathematica
    Table[7 2^Floor[n/2] - (3/2) (3 + (-1)^n), {n, 0, 40}] (* Bruno Berselli, Apr 13 2013 *)
    LinearRecurrence[{0, 3, 0, -2}, {1, 4, 8, 11}, 40] (* T. D. Noe, Apr 17 2013 *)

Formula

G.f.: (1+4*x+5*x^2-x^3)/((1-x)*(1+x)*(1-2*x^2)).
a(2n) = 7*2^n - 6 = A048489(n) = A063757(2n) = A005009(n)-6.
a(2n+1) = 7*2^n - 3 = A048489(n) + 3 = A063757(2n+1) - 3*A000225(n) = A005009(n)-3.
a(n) = a(n-1)*2 if n even.
a(n) = a(n-1)+3 if n odd.
a(n) = 3*a(n-2) - 2*a(n-4) with a(0)=1, a(1)=4, a(2)=8, a(3)=11.
a(n) = 7*2^floor(n/2) - (3/2)*(3+(-1)^n).
a(n) = A047290(A083416(n+1)). [Bruno Berselli, Apr 13 2013]
Showing 1-6 of 6 results.