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%I #12 Jan 07 2020 23:51:20
%S 6,210,110,2730,17,19,10626,26,26970,39270,54834,74046,2162,51,53,55,
%T 195054,3782,287430,342930,5402,474474,6806,635970,89,91,830490,97,
%U 1061106,1190910,1330890,1481430,14042,15006,127,2196870,17822,2627934
%N Product of the n-th run of squarefree numbers.
%C All terms are squarefree;
%C a(n) mod A072284(n) = 0;
%C A136743(n) = A001221(a(n)).
%H Robert Israel, <a href="/A136742/b136742.txt">Table of n, a(n) for n = 1..10000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Squarefree.html">Squarefree</a>
%F a(n) = Product_{k=0..A120992(n)-1} (A072284(n)+k).
%e n=10: A072284(10)=33, A120992(10)=3: a(10)=33*34*35=39270.
%p R:= NULL:
%p state:= false:
%p count:= 0:
%p for n from 1 while count < 100 do
%p if numtheory:-issqrfree(n) then
%p if state then P:= P*n
%p else P:= n; state:= true
%p fi
%p elif state then
%p R:= R, P;
%p count:= count+1;
%p state:= false
%p fi
%p od:
%p R; # _Robert Israel_, Jan 06 2020
%t Times @@ # & /@ DeleteCases[#, _?(! SquareFreeQ@ First@ # &)] &@ SplitBy[Range[140], SquareFreeQ] (* _Michael De Vlieger_, Jan 06 2020 *)
%Y Cf. A005117.
%K nonn
%O 1,1
%A _Reinhard Zumkeller_, Jan 20 2008
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