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%I #15 Feb 22 2021 03:15:59
%S 2,30,42,110,182,506,1406,2162,3422,3782,4290,4830,5402,6006,6806,
%T 11130,11342,12210,13110,16770,23870,24806,27390,27722,31862,33306,
%U 34410,34782,37442,37830,44310,49062,51302,56406,60762,64770,66822,68906
%N Squarefree oblong (pronic) numbers having an odd number of prime factors.
%H Amiram Eldar, <a href="/A098827/b098827.txt">Table of n, a(n) for n = 1..10000</a>
%e a(1)=2 is oblong and squarefree.
%p ts_nsq_pronic:=proc(n) local i, ans; ans:=[ ]: for i from 1 to n do if (numtheory[mobius]( i*(i+1) ) = -1 ) then ans:=[ op(ans),i*(i+1)]: fi od; RETURN(ans) end: ts_nsq_pronic(500);
%t Select[#*(# + 1) & /@ Range[250], MoebiusMu[#1] == -1 &] (* _Amiram Eldar_, Feb 22 2021 *)
%Y Intersection of A002378 or A229882 with A030059.
%Y Cf. A005117.
%K nonn
%O 1,1
%A _Jani Melik_, Oct 09 2004
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