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A257891 Numbers that are products of at least three consecutive primes. 2
30, 105, 210, 385, 1001, 1155, 2310, 2431, 4199, 5005, 7429, 12673, 15015, 17017, 20677, 30030, 33263, 46189, 47027, 65231, 82861, 85085, 96577, 107113, 146969, 190747, 215441, 241133, 255255, 290177, 323323, 347261, 392863, 409457, 478661, 510510, 583573 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..1000

EXAMPLE

a(5) = 1001 = 7 * 11 * 13;

a(6) = 1155 = 3 * 5 * 7 * 11;

a(7) = 2310 = 2 * 3 * 5 * 7 * 11;

a(8) = 2431 = 11 * 13 * 17.

PROG

(Haskell)

import Data.Set (singleton, deleteFindMin, insert)

a257891 n = a257891_list !! (n-1)

a257891_list = f $ singleton (30, 2, 5) where

   f s = y : f (insert (w, p, q') $ insert (w `div` p, a151800 p, q') s')

         where w = y * q'; q' = a151800 q

               ((y, p, q), s') = deleteFindMin s

CROSSREFS

Cf. A151800, A097889, A000977, A046301 (subsequence).

Sequence in context: A101056 A316362 A081370 * A158445 A046301 A193873

Adjacent sequences:  A257888 A257889 A257890 * A257892 A257893 A257894

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, May 12 2015

STATUS

approved

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Last modified July 19 09:33 EDT 2019. Contains 325155 sequences. (Running on oeis4.)