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A036333
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Composite numbers n such that juxtaposition of prime factors of n has length 9.
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2
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512, 768, 1152, 1280, 1408, 1664, 1728, 1792, 1920, 2112, 2176, 2432, 2496, 2592, 2688, 2880, 2944, 3168, 3200, 3264, 3520, 3648, 3712, 3744, 3872, 3888, 3968, 4032, 4160, 4320, 4416, 4480, 4576, 4736, 4752, 4800, 4896, 4928, 5248, 5280, 5408, 5440
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OFFSET
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1,1
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COMMENTS
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The last term is a(84018465) = 997210243 = 9973 * 99991. - Giovanni Resta, Mar 21 2013
Prime factors counted with multiplicity. - Harvey P. Dale, Jul 26 2017
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LINKS
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MAPLE
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isA036333 := proc(n) local d: d:=ifactors(n)[2]: return `if`(not isprime(n) and add(length(d[j][1])*d[j][2], j=1..nops(d))=9, n, NULL): end: seq(isA036333(n), n=2..5440); # Nathaniel Johnston, Jun 22 2011
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MATHEMATICA
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jpf9Q[n_]:=CompositeQ[n]&&Total[IntegerLength[#[[1]]]#[[2]]&/@ FactorInteger[ n]]==9; Select[ Range[6000], jpf9Q] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jul 26 2017 *)
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CROSSREFS
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KEYWORD
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nonn,base,fini,easy
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AUTHOR
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STATUS
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approved
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