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A141091 Integral quotients of products of consecutive composites divided by their sums: sums (divisors). 6

%I #15 Jan 12 2020 09:56:05

%S 4,27,63,112,175,224,250,400,847,896,2368,2448,2695,3596,4300,4624,

%T 4961,5076,5546,6032,6156,6664,8750,9048,9200,9976,10295,11620,12312,

%U 13572,14697,15872,16275,18139,18352,23572,24304,25544,26814,27072,29986

%N Integral quotients of products of consecutive composites divided by their sums: sums (divisors).

%H Amiram Eldar, <a href="/A141091/b141091.txt">Table of n, a(n) for n = 1..10000</a>

%F Find the products and sums of consecutive composites. When the products divided by the sums produce integral quotients, add terms to sequence.

%e a(3) = 63 because 4*6*8*9*10*12*14 = 2903040 and 4+6+8+9+10+12+14 = 63; 2903040/63 = 46080, integral -- 63 is added to the sequence.

%t comp = Select[Range[500], CompositeQ]; sum = Accumulate[comp]; sum[[Position[ Rest@FoldList[Times, 1, comp]/sum, _?IntegerQ] // Flatten]] (* _Amiram Eldar_, Jan 12 2020 *)

%Y Cf. A196415, A141089, A141090, A141092.

%Y Compare with A140761, A159578, A140763, A116536.

%K easy,nonn

%O 1,1

%A _Enoch Haga_, Jun 01 2008

%E a(37) corrected by _Amiram Eldar_, Jan 12 2020

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