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A036330 Composite numbers n such that juxtaposition of prime factors of n has length 6. 1
64, 96, 144, 160, 176, 208, 216, 224, 240, 264, 272, 304, 312, 324, 336, 360, 368, 396, 400, 408, 440, 456, 464, 468, 484, 486, 496, 504, 520, 540, 552, 560, 572, 592, 594, 600, 612, 616, 656, 660, 676, 680, 684, 688, 696, 702, 726, 728, 729, 744, 748, 752 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The last term of this sequence is a(96411)=994009.

LINKS

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

MAPLE

isA036330 := 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))=6, n, NULL): end: seq(isA036330(n), n=2..752); # Nathaniel Johnston, Jun 22 2011

MATHEMATICA

pf6Q[n_]:=!PrimeQ[n]&&Total[Last[#]IntegerLength[First[#]]&/@FactorInteger[ n]]==6; Select[Range[800], pf6Q]  (* Harvey P. Dale, Jun 19 2012 *)

CROSSREFS

Cf. A036326-A036334.

Sequence in context: A114417 A046305 A114828 * A046306 A223086 A175163

Adjacent sequences:  A036327 A036328 A036329 * A036331 A036332 A036333

KEYWORD

nonn,base,fini,easy

AUTHOR

Patrick De Geest, Dec 15 1998

STATUS

approved

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Last modified April 22 22:19 EDT 2021. Contains 343197 sequences. (Running on oeis4.)