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A359127
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Oblong numbers which are products of six distinct primes.
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0
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43890, 53130, 81510, 108570, 152490, 184470, 188790, 260610, 297570, 371490, 416670, 475410, 509082, 549822, 593670, 637602, 648830, 756030, 757770, 814506, 932190, 939930, 973182, 1003002, 1045506, 1135290, 1178310, 1222130, 1233210, 1257762, 1278030, 1332870, 1414910, 1417290, 1484742
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OFFSET
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1,1
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LINKS
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EXAMPLE
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43890 = 209*210 = 2*3*5*7*11*19
53130 = 230*231 = 2*3*5*7*11*23
81510 = 285*286 = 2*3*5*11*13*19
108570 = 329*330 = 2*3*5*7*11*47
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MAPLE
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R:= NULL: count:= 0:
for n from 1 while count < 100 do
x:= n*(n+1);
F:= ifactors(x)[2];
if nops(F) = 6 and max(map(t -> t[2], F))=1 then
R:= R, x; count:= count+1;
fi
od:
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MATHEMATICA
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Select[(#*(# + 1)) & /@ Range[1250], FactorInteger[#][[;; , 2]] == {1, 1, 1, 1, 1, 1} &] (* Amiram Eldar, Dec 26 2022 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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