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A114405 5-almost prime gaps. First differences of A014614. 4
16, 24, 8, 28, 4, 8, 42, 6, 8, 4, 20, 8, 35, 9, 12, 6, 2, 8, 20, 4, 8, 56, 10, 14, 4, 9, 3, 12, 20, 10, 6, 8, 4, 28, 4, 20, 32, 15, 21, 4, 2, 18, 4, 14, 26, 4, 15, 5, 4, 4, 8, 4, 2, 26, 16, 6, 2, 8, 20, 48, 20, 34, 6, 3, 27, 2, 4, 20, 1, 7, 16, 8, 4, 4, 6, 30, 6, 6, 12, 6, 3, 11 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

First occurrences of a(n)=1,2,3,.. are at n=69, 17, 27, 5, 48, 8, 70, 3, 14, 23, 82, 15, 150, 24, 38, 1, 172, 42, 258, 11, 39, 135, 102, 2, 779, 45, 65, 4, 518, 76, 263, 37, 211, 62, 13, 1009, 2463, 606, 254, 151, 3348, 7, 4513,... - R. J. Mathar, Oct 06 2007

LINKS

R. J. Mathar, Table of n, a(n) for n = 1..9999

FORMULA

a(n) = A014614(n+1) - A014614(n).

EXAMPLE

a(1) = 16 = 48-32 where 32 is the first 5-almost prime and 48 is the second.

a(2) = 24 = 72-48.

a(3) = 8 = 80-72.

a(4) = 28 = 108-80.

a(5) = 4 = 112-108.

a(6) = 8 = 120-112.

a(7) = 42 = 162-120.

a(8) = 6 = 168-162.

a(13) = 35 = 243-208.

a(22) = 56 = 368-312.

MATHEMATICA

Differences[Select[Range[2000], PrimeOmega[#]==5&]] (* Harvey P. Dale, Sep 28 2019 *)

CROSSREFS

Cf. A014614, A065516, A111870, A111871, A114403-A114411, A114412-A114422.

Sequence in context: A225929 A179370 A166675 * A098351 A206267 A325480

Adjacent sequences:  A114402 A114403 A114404 * A114406 A114407 A114408

KEYWORD

easy,nonn

AUTHOR

Jonathan Vos Post, Nov 25 2005

EXTENSIONS

More terms from R. J. Mathar, Oct 06 2007

STATUS

approved

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Last modified February 28 06:55 EST 2020. Contains 332321 sequences. (Running on oeis4.)