A114407 7-almost prime gaps. First differences of A046308.

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

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