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Integral quotients of products of consecutive composites divided by their sums: Last consecutive composite.
5

%I #15 Jan 12 2020 09:55:44

%S 4,9,14,18,22,25,26,33,48,49,78,80,84,95,105,110,114,115,119,123,124,

%T 129,147,150,152,158,160,170,175,184,190,200,202,212,213,242,245,250,

%U 256,258,272,284,287,288,291,306,309,314,319,327,332,333,336,342,343

%N Integral quotients of products of consecutive composites divided by their sums: Last consecutive composite.

%H Amiram Eldar, <a href="/A141089/b141089.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) = 14 because 4*6*8*9*10*12*14 = 2903040 and 4+6+8+9+10+12+14 = 63; 2903040/63 = 46080, integral -- 14 is added to the sequence.

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

%Y Cf. A141090, A141091, A141092.

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

%K easy,nonn

%O 1,1

%A _Enoch Haga_, Jun 01 2008