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A036333 Composite numbers n such that juxtaposition of prime factors of n has length 9. 2
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

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

LINKS

Nathaniel Johnston, Table of n, a(n) for n = 1..10000

MAPLE

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

MATHEMATICA

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 *)

CROSSREFS

Cf. A036326-A036334.

Sequence in context: A248536 A202461 A046311 * A046312 A045033 A066648

Adjacent sequences:  A036330 A036331 A036332 * A036334 A036335 A036336

KEYWORD

nonn,base,fini,easy

AUTHOR

Patrick De Geest, Dec 15 1998.

STATUS

approved

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Last modified January 17 10:29 EST 2019. Contains 319218 sequences. (Running on oeis4.)