A359127 Oblong numbers which are products of six distinct primes.
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
Offset: 1
Keywords
Examples
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
Programs
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Maple
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: R; # Robert Israel, Dec 26 2022 -
Mathematica
Select[(#*(# + 1)) & /@ Range[1250], FactorInteger[#][[;; , 2]] == {1, 1, 1, 1, 1, 1} &] (* Amiram Eldar, Dec 26 2022 *)