login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A114407 7-almost prime gaps. First differences of A046308. 2
64, 96, 32, 112, 16, 32, 168, 24, 32, 16, 80, 32, 140, 36, 48, 24, 8, 32, 80, 16, 32, 210, 14, 40, 56, 16, 36, 12, 48, 80, 40, 24, 32, 16, 112, 16, 80, 107, 21, 60, 84, 16, 8, 54, 18, 16, 56, 104, 16, 60, 20, 16, 16, 32, 16, 8, 104, 64, 24, 8, 32, 80, 192, 80, 10, 126, 24, 12 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Zak Seidov, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = A046308(n+1) - A046308(n).

EXAMPLE

a(1) = 64 = 192-128 where 128 is the first 7-almost prime and 192 is the second.

a(2) = 96 = 288-192.

a(3) = 32 = 320-288.

a(4) = 112 = 432-320.

a(5) = 16 = 448-432.

a(6) = 32 = 480-448.

a(7) = 168 = 648-480.

a(8) = 24 = 672-648.

MATHEMATICA

Differences[Select[Range[10000], PrimeOmega[#]==7&]] (* Harvey P. Dale, Oct 13 2019 *)

CROSSREFS

Cf. A046308, A065516, A111870, A111871, A114403-A114411, A114412-A114422.

Sequence in context: A240527 A262743 A176819 * A259942 A114417 A046305

Adjacent sequences:  A114404 A114405 A114406 * A114408 A114409 A114410

KEYWORD

easy,nonn

AUTHOR

Jonathan Vos Post, Nov 25 2005

EXTENSIONS

Corrected and extended by R. J. Mathar, Aug 31 2007

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 24 05:09 EDT 2021. Contains 345416 sequences. (Running on oeis4.)