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A141091
Integral quotients of products of consecutive composites divided by their sums: sums (divisors).
6
4, 27, 63, 112, 175, 224, 250, 400, 847, 896, 2368, 2448, 2695, 3596, 4300, 4624, 4961, 5076, 5546, 6032, 6156, 6664, 8750, 9048, 9200, 9976, 10295, 11620, 12312, 13572, 14697, 15872, 16275, 18139, 18352, 23572, 24304, 25544, 26814, 27072, 29986
OFFSET
1,1
LINKS
FORMULA
Find the products and sums of consecutive composites. When the products divided by the sums produce integral quotients, add terms to sequence.
EXAMPLE
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.
MATHEMATICA
comp = Select[Range[500], CompositeQ]; sum = Accumulate[comp]; sum[[Position[ Rest@FoldList[Times, 1, comp]/sum, _?IntegerQ] // Flatten]] (* Amiram Eldar, Jan 12 2020 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Enoch Haga, Jun 01 2008
EXTENSIONS
a(37) corrected by Amiram Eldar, Jan 12 2020
STATUS
approved