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

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 56th year, we are closing in on 350,000 sequences, and we’ve crossed 9,700 citations (which often say “discovered thanks to the OEIS”).

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A075585 Primes p such that the number of distinct prime divisors of all composite numbers between p and the next prime is 5. 10
19, 23, 37, 43, 97, 127, 223, 499, 673, 1213, 2309, 2729, 6089, 6269, 7589, 8969, 9239, 9281, 10709, 11549, 11969, 12539, 13397, 14321, 15329, 16829, 17489, 18059, 19139, 19379, 19469, 19889, 20747, 21317, 21839, 22109, 22619, 23369, 23561, 24179 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

MATHEMATICA

dpd5Q[p_]:=Length[Union[Flatten[FactorInteger[#][[All, 1]]&/@Range[ p+1, NextPrime[ p]-1]]]]==5; Select[Prime[Range[3000]], dpd5Q] (* Harvey P. Dale, Aug 11 2021 *)

PROG

(MAGMA) a:=[]; for k in PrimesInInterval(2, 25000) do b:={}; for s in [k..NextPrime(k)-1] do if not IsPrime(s) then b:=b join Set(PrimeDivisors(s)); end if; end for; if #Set(b) eq 5 then  Append(~a, k); end if; end for; a; // Marius A. Burtea, Sep 26 2019

CROSSREFS

Cf. A052297, A075581, A075580, A059960, A075583, A075584, A075586, A075587, A075588, A075589.

Sequence in context: A343741 A060269 A245382 * A052030 A045297 A039292

Adjacent sequences:  A075582 A075583 A075584 * A075586 A075587 A075588

KEYWORD

nonn

AUTHOR

Amarnath Murthy, Sep 26 2002

EXTENSIONS

More terms from Sam Alexander, Oct 21 2003

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 December 1 05:33 EST 2021. Contains 349426 sequences. (Running on oeis4.)