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A257891 Numbers that are products of at least three consecutive primes.

%I A257891 #6 Aug 04 2024 15:43:06
%S A257891 30,105,210,385,1001,1155,2310,2431,4199,5005,7429,12673,15015,17017,
%T A257891 20677,30030,33263,46189,47027,65231,82861,85085,96577,107113,146969,
%U A257891 190747,215441,241133,255255,290177,323323,347261,392863,409457,478661,510510,583573
%N A257891 Numbers that are products of at least three consecutive primes.
%H A257891 Reinhard Zumkeller, <a href="/A257891/b257891.txt">Table of n, a(n) for n = 1..1000</a>
%e A257891 a(5) = 1001 = 7 * 11 * 13;
%e A257891 a(6) = 1155 = 3 * 5 * 7 * 11;
%e A257891 a(7) = 2310 = 2 * 3 * 5 * 7 * 11;
%e A257891 a(8) = 2431 = 11 * 13 * 17.
%t A257891 Select[Module[{nn=1000},Flatten[Table[Times@@@Partition[Prime[Range[nn]],d,1],{d,3,7}]]]//Union,#<10^7&] (* _Harvey P. Dale_, Aug 04 2024 *)
%o A257891 (Haskell)
%o A257891 import Data.Set (singleton, deleteFindMin, insert)
%o A257891 a257891 n = a257891_list !! (n-1)
%o A257891 a257891_list = f $ singleton (30, 2, 5) where
%o A257891    f s = y : f (insert (w, p, q') $ insert (w `div` p, a151800 p, q') s')
%o A257891          where w = y * q'; q' = a151800 q
%o A257891                ((y, p, q), s') = deleteFindMin s
%Y A257891 Cf. A151800, A097889, A000977, A046301 (subsequence).
%K A257891 nonn
%O A257891 1,1
%A A257891 _Reinhard Zumkeller_, May 12 2015