login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A210998 Composite numbers that are in the gap between an even-indexed prime and an odd-indexed prime. 2
4, 8, 9, 10, 14, 15, 16, 20, 21, 22, 30, 38, 39, 40, 44, 45, 46, 54, 55, 56, 57, 58, 62, 63, 64, 65, 66, 72, 80, 81, 82, 90, 91, 92, 93, 94, 95, 96, 102, 108, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 132, 133, 134, 135, 136 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
EXAMPLE
Illustration of initial terms of three sequences:
A210998: 4, 8, 9, 10, 14, 15, 16
A000040: 2, 3, 5, 7, 11, 13,
A210999: 6, 12,
MATHEMATICA
Select[Range[4, 200], Not[PrimeQ[#]] && EvenQ[PrimePi[#]] &] (* Alonso del Arte, Sep 26 2012 *)
CROSSREFS
Sequence in context: A080970 A288862 A274584 * A205524 A125493 A341615
KEYWORD
nonn,easy
AUTHOR
Omar E. Pol, Sep 26 2012
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 18 04:56 EDT 2024. Contains 371767 sequences. (Running on oeis4.)