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A033477 Products p^3 or p^2*q, where {p,q} are consecutive primes.

%I A033477 #11 Jun 26 2020 23:45:02
%S A033477 8,12,18,27,45,75,125,175,245,343,539,847,1331,1573,1859,2197,2873,
%T A033477 3757,4913,5491,6137,6859,8303,10051,12167,15341,19343,24389,26071,
%U A033477 27869,29791,35557,42439,50653,56129,62197,68921,72283,75809,79507,86903,94987,103823
%N A033477 Products p^3 or p^2*q, where {p,q} are consecutive primes.
%H A033477 Robert Israel, <a href="/A033477/b033477.txt">Table of n, a(n) for n = 0..10000</a>
%F A033477 From _Robert Israel_, Jun 26 2020: (Start)
%F A033477 a(3k) = A030078(k+1).
%F A033477 a(3k+1) = A251720(k+1).
%F A033477 a(3k+2) = a(3k+1)^2/a(3k). (End)
%p A033477 R:= NULL: p:= 2:
%p A033477 for n from 1 to 30 do
%p A033477   q:= nextprime(p);
%p A033477   R:= R, p^3, p^2*q, p*q^2;
%p A033477   p:= q;
%p A033477 od:
%p A033477 R; # _Robert Israel_, Jun 26 2020
%t A033477 nn=50;With[{prs=Prime[Range[nn]]},Take[Union[Flatten[{prs^3,{#[[1]]^2 #[[2]],#[[2]]^2 #[[1]]}&/@Partition[prs,2,1]}]],nn]] (* _Harvey P. Dale_, Dec 28 2013 *)
%Y A033477 Cf. A030078, A251720.
%K A033477 nonn
%O A033477 0,1
%A A033477 _Jeff Burch_
%E A033477 Corrected and extended by _Harvey P. Dale_, Dec 28 2013