The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A138885 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A138885

n-th run has length n-th nonprime number, with digits 0 and 1 only, starting with 1.
(history; published version)

#5 by Harvey P. Dale at Fri May 26 17:44:13 EDT 2023

STATUS

editing

approved

#4 by Harvey P. Dale at Fri May 26 17:44:11 EDT 2023

MATHEMATICA

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

STATUS

approved

editing

#3 by Russ Cox at Fri Mar 30 17:33:54 EDT 2012

AUTHOR

_Omar E. Pol (info(AT)polprimos.com), _, Apr 06 2008

Discussion

Fri Mar 30

17:33

OEIS Server: https://oeis.org/edit/global/157

#2 by N. J. A. Sloane at Tue Jun 01 03:00:00 EDT 2010

EXAMPLE

.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

KEYWORD

easy,nonn,new

#1 by N. J. A. Sloane at Sun Jun 29 03:00:00 EDT 2008

NAME

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

DATA

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

1,1

EXAMPLE

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.

KEYWORD

easy,nonn

AUTHOR

Omar E. Pol (info(AT)polprimos.com), Apr 06 2008

STATUS

approved