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.

A097053 First occurrence of n in A097051.

Original entry on oeis.org

1, 2, 3, 8, 10, 12, 14, 32, 36, 40, 44, 48, 52, 56, 60, 128, 136, 144, 152, 160, 168, 176, 184, 192, 200, 208, 216, 224, 232, 240, 248, 512, 528, 544, 560, 576, 592, 608, 624, 640, 656, 672, 688, 704, 720, 736, 752, 768, 784, 800, 816, 832, 848, 864, 880, 896
Offset: 1

Views

Author

Keywords

Crossrefs

Cf. A097051.

Programs

  • Mathematica
    a[1] = 1; a[n_] := a[n] = Floor[ n / a[ Floor[n / 2]]]; t = Table[ a[n], {n, 1000}]; b[n_] := Block[{p = Position[t, n, 1, 1]}, If[p == {}, 0, p]]; Flatten[ Table[ b[n], {n, 60}]]

Formula

For n>1, a(n) = A053644(n) * n / 2.

Extensions

Formula added by Max Alekseyev, Mar 02 2011

A096036 a(n) = ceiling(n/a(ceiling(n/2))); a(1) = 1.

Original entry on oeis.org

1, 2, 2, 2, 3, 3, 4, 4, 3, 4, 4, 4, 4, 4, 4, 4, 6, 6, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8, 8, 6, 6, 6, 6, 8, 8, 8, 8, 7, 7, 8, 8, 8, 8, 8, 8, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 11, 11, 12, 12, 12, 12, 12, 12, 10, 10, 10, 10, 10, 10, 10, 10, 12, 12, 12, 12, 11, 11, 11, 11, 12, 12, 12
Offset: 1

Views

Author

Reinhard Zumkeller, Jul 20 2004

Keywords

Examples

			a(50)=ceiling(50/a(25))
..... a(25)=ceiling(25/a(13))
........... a(13)=ceiling(13/a(7))
................. a(7)=ceiling(7/a(4))
...................... a(4)=ceiling(4/a(2))
........................... a(2)=ceiling(2/a(1))
................................ a(1)=1
........................... a(2)=ceiling(2/a(1))=ceiling(2/1)=2
...................... a(4)=ceiling(4/a(2))=ceiling(4/2)=2
................. a(7)=ceiling(7/a(4))=ceiling(7/2)=4
........... a(13)=ceiling(13/a(7))=ceiling(13/4)=4
..... a(25)=ceiling(25/a(13))=ceiling(25/4)=7
a(50)=ceiling(50/a(25))=ceiling(50/7)=8.
		

Crossrefs

Programs

  • Mathematica
    a[1] = 1; a[n_] := a[n] = Ceiling[ n / a[Ceiling[ n/2]]]; Table[ a[n], {n, 91}] (* Robert G. Wilson v, Jul 21 2004 *)

A372970 a(1)=1, then a(n) = floor(n/max(a(n-1),a(floor(n/2)))).

Original entry on oeis.org

1, 2, 1, 2, 2, 3, 2, 4, 2, 5, 2, 4, 3, 4, 3, 4, 4, 4, 4, 4, 4, 5, 4, 6, 4, 6, 4, 7, 4, 7, 4, 8, 4, 8, 4, 9, 4, 9, 4, 10, 4, 10, 4, 8, 5, 9, 5, 8, 6, 8, 6, 8, 6, 9, 6, 8, 7, 8, 7, 8, 7, 8, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 9, 8, 8, 8, 9, 8, 8, 8, 10, 8, 8, 8, 10, 8, 11, 8, 11, 8, 10, 9, 10, 9, 10, 9, 10, 9, 11
Offset: 1

Views

Author

Benoit Cloitre, May 18 2024

Keywords

Comments

It seems that limsup and liminf of a(n)/sqrt(n) exist (see link).

Crossrefs

Programs

  • PARI
    a(n)=if(n<2,1,floor(n/max(a(n-1),a(n\2))))

A372971 a(1)=1, then a(n) = floor(n/min(a(n-1),a(floor(n/2)))).

Original entry on oeis.org

1, 2, 3, 2, 2, 3, 2, 4, 4, 5, 5, 4, 4, 7, 7, 4, 4, 4, 4, 5, 4, 5, 4, 6, 6, 6, 6, 4, 7, 4, 7, 8, 8, 8, 8, 9, 9, 9, 9, 8, 8, 10, 10, 8, 9, 11, 11, 8, 8, 8, 8, 8, 8, 9, 9, 14, 14, 8, 8, 15, 15, 8, 9, 8, 8, 8, 8, 8, 8, 8, 8, 9, 8, 9, 8, 9, 8, 9, 8, 10
Offset: 1

Views

Author

Benoit Cloitre, May 18 2024

Keywords

Comments

It seems that limsup and liminf of a(n)/sqrt(n) exist (see link).

Crossrefs

Programs

  • Mathematica
    a[1]=1; a[n_]:=Floor[n/Min[a[n-1],a[Floor[n/2]]]]; Array[a,80] (* Stefano Spezia, May 18 2024 *)
  • PARI
    a(n)=if(n<2,1,floor(n/min(a(n-1),a(n\2))))
Showing 1-4 of 4 results.