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.

A138711 n-th run has length n-th positive triangular number, with digits 0 and 1 only, starting with 1.

Original entry on oeis.org

1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
Offset: 1

Views

Author

Omar E. Pol, Mar 29 2008

Keywords

Examples

			.n ..... Run ............................... Length
.1 ..... 1 ................................. 1
.2 ..... 0,0,0 ............................. 3
.3 ..... 1,1,1,1,1,1........................ 6
.4 ..... 0,0,0,0,0,0,0,0,0,0 ............... 10
.5 ..... 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1 ..... 15

Crossrefs

Cf. A000217, A057211, A138149, A138709.

Programs

  • Mathematica
    Flatten[Table[Join[PadRight[{},(n(n+1))/2,1],PadRight[{},((n+1)(n+2))/2, 0]],{n,1,7,2}]] (* Harvey P. Dale, Dec 11 2011 *)

A138719 Concatenation of k digits 1, k digits 0 and k digits 1, where k is the n-th positive Fibonacci number.

Original entry on oeis.org

101, 101, 110011, 111000111, 111110000011111, 111111110000000011111111, 111111111111100000000000001111111111111, 111111111111111111111000000000000000000000111111111111111111111
Offset: 1

Views

Author

Omar E. Pol, Mar 29 2008

Keywords

Crossrefs

Cf. A000045, A134803, A138709, A138722.

A138885 n-th run has length n-th nonprime number, with digits 0 and 1 only, starting with 1.

Original entry on oeis.org

1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
Offset: 1

Views

Author

Omar E. Pol, Apr 06 2008

Keywords

Examples

			.n ..... Run ................... Length
.1 ..... 1 ..................... 1
.2 ..... 0,0,0,0 ............... 4
.3 ..... 1,1,1,1,1,1 ........... 6
.4 ..... 0,0,0,0,0,0,0,0 ....... 8
.5 ..... 1,1,1,1,1,1,1,1,1 ..... 9

Crossrefs

Nonprime numbers: A018252. Cf. A057211, A138149, A138150, A138709, A138710, A138711, A138712, A138886.

Programs

  • Mathematica
    Join[{1},{PadRight[{},#[[1]],0],PadRight[{},#[[2]],1]}&/@Partition[Select[Range[ 20],CompositeQ],2]]//Flatten (* Harvey P. Dale, May 26 2023 *)

A138886 n-th run has length n-th nonprime number A018252, with digits 0 and 1 only, starting with 0.

Original entry on oeis.org

0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
Offset: 1

Views

Author

Omar E. Pol, Apr 06 2008

Keywords

Comments

Also the n-th run has length A141468, with digits 0 and 1 only, starting with 1.

Examples

			.n ..... Run ................... Length
.1 ..... 0 ..................... 1
.2 ..... 1,1,1,1 ............... 4
.3 ..... 0,0,0,0,0,0 ........... 6
.4 ..... 1,1,1,1,1,1,1,1 ....... 8
.5 ..... 0,0,0,0,0,0,0,0,0 ..... 9

Crossrefs

Cf. A057211, A138149, A138150, A138709, A138710, A138711, A138712, A138885.
Showing 1-4 of 4 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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