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%I #12 Sep 28 2016 18:22:05
%S 4,9,12,16,18,20,25,28,32,36,42,44,45,48,49,50,52,54,60,63,66,68,72,
%T 75,76,78,80,81,84,88,90,92,96,98,99,100,102,104,108,110,112,114,116,
%U 117,121,124,126,128,130,132,136,138,140,147,148,150,152,153,156,160,162
%N n is not equal to the product of the k smallest divisors of n for any k.
%C Positive integers not included in A072510. Sequence includes all squares of primes.
%H Robert Israel, <a href="/A072498/b072498.txt">Table of n, a(n) for n = 1..10000</a>
%e Divisors of 384 are 1,2,3,4,6,8,12,16,24,32,48,64,96,128,192,384. Partial products are: 1=1, 1*2=2, 1*2*3=6, 1*2*3*4=24, 1*2*3*4*6=144, 1*2*3*4*6*8=1152 and so 384 (144<384<1152) is not in A072510.
%p filter:= proc(n) local F,d,p;
%p F:= sort(convert(numtheory:-divisors(n),list));
%p p:= 1:
%p for d in F do
%p p:= p*d;
%p if p > n then return true
%p elif p = n then return false
%p fi
%p od;
%p end proc:
%p select(filter, [$1..1000]); # _Robert Israel_, Sep 28 2016
%t Select[Range[200],!MemberQ[FoldList[Times,1,Divisors[#]],#]&] (* _Harvey P. Dale_, Jun 18 2013 *)
%Y Cf. A072510.
%K nonn
%O 1,1
%A _Vladimir Baltic_, Aug 03 2002
%E Edited by _Robert Israel_, Sep 28 2016
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