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A069277
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16-almost primes (generalization of semiprimes).
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29
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65536, 98304, 147456, 163840, 221184, 229376, 245760, 331776, 344064, 360448, 368640, 409600, 425984, 497664, 516096, 540672, 552960, 557056, 573440, 614400, 622592, 638976, 746496, 753664, 774144, 802816, 811008, 829440, 835584, 860160
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OFFSET
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1,1
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COMMENTS
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Product of 16 not necessarily distinct primes.
Divisible by exactly 16 prime powers (not including 1).
Any 16-almost prime can be represented in several ways as a product of two 8-almost primes A046310; in several ways as a product of four 4-almost primes A014613; and in several ways as a product of eight semiprimes A001358. - Jonathan Vos Post, Dec 12 2004
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LINKS
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FORMULA
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Product p_i^e_i with Sum e_i = 16.
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MATHEMATICA
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Select[Range[10^6], PrimeOmega[#]==16&] (* Harvey P. Dale, Jan 30 2015 *)
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PROG
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(PARI) k=16; start=2^k; finish=1000000; v=[] for(n=start, finish, if(bigomega(n)==k, v=concat(v, n))); v
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CROSSREFS
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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), A014614 (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), this sequence (r = 16), A069278 (r = 17), A069279 (r = 18), A069280 (r = 19), A069281 (r = 20). - Jason Kimberley, Oct 02 2011
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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