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 A014614 Numbers that are products of 5 primes (or 5-almost primes, a generalization of semiprimes). 90
 32, 48, 72, 80, 108, 112, 120, 162, 168, 176, 180, 200, 208, 243, 252, 264, 270, 272, 280, 300, 304, 312, 368, 378, 392, 396, 405, 408, 420, 440, 450, 456, 464, 468, 496, 500, 520, 552, 567, 588, 592, 594, 612, 616, 630, 656, 660, 675, 680, 684, 688, 696 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Divisible by exactly 5 prime powers (not including 1). LINKS T. D. Noe, Table of n, a(n) for n = 1..10000 Eric Weisstein's World of Mathematics, Almost Prime FORMULA Product p_i^e_i with sum e_i = 5. a(n) ~ 24n log n/(log log n)^4. - Charles R Greathouse IV, Mar 20 2013 a(n) = A078840(5,n). - R. J. Mathar, Jan 30 2019 MATHEMATICA Select[Range, Plus @@ Last /@ FactorInteger[ # ] == 5 &] (* Vladimir Joseph Stephan Orlovsky, Apr 23 2008 *) PROG (PARI) is(n)=bigomega(n)==5 \\ Charles R Greathouse IV, Mar 20 2013 CROSSREFS Cf. A046304, A114453 (number of 5-almost primes <= 10^n). Sequences listing r-almost primes, that is, the n such that A001222(n) = r: A000040 (r = 1), A001358 (r = 2), A014612 (r = 3), A014613 (r = 4), this sequence (r = 5), A046306 (r = 6), A046308 (r = 7), A046310 (r = 8), A046312 (r = 9), A046314 (r = 10), A069272 (r = 11), A069273 (r = 12), A069274 (r = 13), A069275 (r = 14), A069276 (r = 15), A069277 (r = 16), A069278 (r = 17), A069279 (r = 18), A069280 (r = 19), A069281 (r = 20). - Jason Kimberley, Oct 02 2011 Sequence in context: A090052 A163285 A036329 * A046371 A175162 A114437 Adjacent sequences:  A014611 A014612 A014613 * A014615 A014616 A014617 KEYWORD nonn AUTHOR EXTENSIONS More terms from Scott Lindhurst (ScottL(AT)alumni.princeton.edu) and Patrick De Geest, Jun 15 1998 STATUS approved

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Last modified April 11 19:49 EDT 2021. Contains 342888 sequences. (Running on oeis4.)