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.

A183163 Least integer k such that floor(k*log(n+1))>k*log(n).

Original entry on oeis.org

2, 1, 3, 2, 3, 5, 1, 6, 4, 3, 5, 2, 5, 3, 4, 5, 6, 10, 18, 1, 11, 8, 6, 5, 4, 7, 10, 3, 5, 7, 9, 15, 2, 11, 7, 5, 8, 14, 3, 10, 7, 4, 9, 5, 11, 6, 7, 8, 10, 12, 15, 21, 34, 1, 40, 24, 17, 13, 11, 10, 8, 7, 13, 6, 11, 5, 14, 9, 17, 4, 11, 7, 10, 13, 22, 3, 17
Offset: 1

Views

Author

Clark Kimberling, Dec 27 2010

Keywords

Comments

Equivalently, a(n) is the least integer k for which there is an integer J such that n^k < e^J < (n+1)^k; or, equivalently, such that there is a rational number H with denominator k for which log(n) < H < log(n+1).

Crossrefs

Cf. A183162.

Programs

  • Mathematica
    Table[k=1; While[Floor[k*Log[n+1]] <= k*Log[n], k++]; k, {n, 100}]
  • Sage
    A183163 = lambda n: next(k for k in IntegerRange(1, infinity) if floor(k*log(n+1)) > k*log(n)) # D. S. McNeil, Dec 28 2010

A275817 Least positive integer s such that an integer square k^2 lies between s^2*n and s^2*(n+1), with s^2*n < k^2 < s^2*(n+1).

Original entry on oeis.org

2, 3, 2, 4, 5, 3, 2, 3, 6, 7, 4, 3, 2, 3, 4, 8, 9, 5, 3, 5, 2, 3, 4, 5, 10, 11, 6, 4, 3, 5, 2, 5, 3, 4, 6, 12, 13, 7, 5, 4, 3, 7, 2, 5, 3, 4, 5, 7, 14, 15, 8, 5, 4, 3, 5, 7, 2, 5, 3, 7, 4, 6, 8, 16, 17, 9, 6, 5, 4, 3, 5, 7, 2, 5, 8, 3, 4, 5, 6, 9, 18, 19, 10, 7, 5, 4, 7, 3
Offset: 0

Views

Author

Hugo Pfoertner, Aug 09 2016

Keywords

Comments

The corresponding values of k are provided in A275818.

Examples

			a(0)=2, because 2^2*0 < 1^2 < 2^2*(0+1).
		

Crossrefs

Programs

  • Mathematica
    Table[s = 1; While[Count[Range[n s^2 + 1, (n + 1) s^2 - 1], k_ /; IntegerQ@ Sqrt@ k] == 0, s++]; s, {n, 0, 120}] (* Michael De Vlieger, Aug 14 2016 *)

Formula

If n = k^2 - 1 and k > 0, then a(n) = 2*k, A183162(n) = 1; otherwise a(n) = A183162(n).

A183164 Least integer k such that k*arctan(n) and k*arctan(n+1) are separated by an integer.

Original entry on oeis.org

1, 5, 4, 3, 5, 7, 9, 11, 13, 19, 27, 41, 85, 2, 61, 43, 33, 29, 25, 23, 21, 19, 36, 17, 32, 15, 43, 28, 41, 13, 76, 50, 37, 24, 35, 46, 57, 101, 11, 97, 64, 53, 42, 31, 51, 71, 111, 20, 69, 49, 78, 29, 67, 105, 38, 47, 103, 56, 74, 83, 101, 128, 182, 299, 9
Offset: 1

Views

Author

Clark Kimberling, Dec 27 2010

Keywords

Comments

a(n) is the least positive integer for which there is a rational number H with denominator k for which n < tan(H) < n+1.

Crossrefs

Programs

  • Mathematica
    Table[k=1; While[Floor[k*ArcTan[n+1]]<=k*ArcTan[n], k++];k,{n,100}]

A183197 Least integer k such that Floor(k*(n+1)^(1/3))>k*n^(1/3).

Original entry on oeis.org

4, 3, 2, 3, 4, 6, 1, 13, 7, 5, 4, 3, 5, 7, 2, 9, 5, 3, 7, 4, 5, 6, 7, 9, 14, 1, 28, 14, 10, 8, 6, 5, 9, 4, 7, 13, 3, 8, 5, 7, 11, 2, 17, 9, 7, 5, 8, 11, 3, 10, 7, 4, 9, 5, 11, 6, 7, 8, 10, 12, 16, 24, 1, 49, 25, 17, 13, 10, 9, 8, 7, 6, 11, 5, 9, 4, 15, 7, 10, 16, 3, 14, 8, 13, 5, 7, 9, 11, 15, 27, 2, 17, 11, 9, 7, 12, 5, 8, 11, 14
Offset: 1

Views

Author

Clark Kimberling, Dec 29 2010

Keywords

Crossrefs

Programs

  • Mathematica
     Table[k=1; While[Floor[k*(n+1)^(1/3)]<=k*n^(1/3), k++]; k,{n,100}]

A183199 Least integer k such that Floor(k*f(n+1))>k*f(n), where f(n)=(n^2)/(1+n^2).

Original entry on oeis.org

3, 6, 11, 18, 27, 38, 51, 66, 83, 102, 123, 146, 171, 198, 227, 258, 291, 326, 363, 402, 443, 486, 531, 578, 627, 678, 731, 786, 843, 902, 963, 1026, 1091, 1158, 1227, 1298, 1371, 1446, 1523, 1602, 1683, 1766, 1851, 1938, 2027, 2118, 2211, 2306, 2403, 2502
Offset: 1

Views

Author

Clark Kimberling, Dec 29 2010

Keywords

Comments

Appears to be essentially the same as A102305, A059100 and A010000. - R. J. Mathar, Jun 07 2011

Crossrefs

Cf. A183162.

Programs

  • Mathematica
    Table[k=1; While[Floor[k*((n+1)^2)/(1+(n+1)^2)]<=k*(n^2)/(1+(n^2)), k++]; k, {n,100}]

A183201 Least integer k such that Floor(k*f(n+1))>k*f(n), where f(n)=arccosh(n).

Original entry on oeis.org

1, 2, 1, 4, 3, 2, 3, 5, 9, 1, 6, 4, 7, 3, 7, 2, 7, 5, 3, 7, 4, 5, 6, 8, 12, 21, 1, 17, 11, 8, 7, 6, 5, 9, 4, 7, 13, 3, 8, 5, 7, 9, 11, 23, 2, 13, 9, 7, 5, 13, 8, 17, 3, 10, 7, 11, 4, 13, 9, 5, 11, 6, 13, 7, 8, 9, 10, 12, 14, 18, 23, 34, 61, 1, 42, 28, 21, 16, 14, 12, 11, 9, 17, 8, 7, 13, 6, 17, 11, 5, 14, 9, 13, 21, 4, 15, 11, 7, 17, 10
Offset: 1

Views

Author

Clark Kimberling, Dec 29 2010

Keywords

Comments

Equivalently, k is the least positive integer such that there is a rational number H with denominator k for which n < cosh(H) < n+1.

Crossrefs

Programs

  • Mathematica
    Table[k=1; While[Floor[k*ArcCosh[n+1]]<=k*ArcCosh[n], k++]; k, {n,100}]
Showing 1-6 of 6 results.