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A069275
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14-almost primes (generalization of semiprimes).
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27
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16384, 24576, 36864, 40960, 55296, 57344, 61440, 82944, 86016, 90112, 92160, 102400, 106496, 124416, 129024, 135168, 138240, 139264, 143360, 153600, 155648, 159744, 186624, 188416, 193536, 200704, 202752, 207360, 208896, 215040, 225280
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OFFSET
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1,1
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COMMENTS
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Product of 14 not necessarily distinct primes.
Divisible by exactly 14 prime powers (not including 1).
Any 14-almost prime can be represented in several ways as a product of two 7-almost primes A046308; and in several ways as a product of seven semiprimes A001358. - Jonathan Vos Post, Dec 11 2004
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LINKS
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D. W. Wilson, Table of n, a(n) for n = 1..10000
Eric Weisstein's World of Mathematics, Almost Prime.
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FORMULA
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Product p_i^e_i with Sum e_i = 14.
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MATHEMATICA
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Select[Range[50000], Plus @@ Last /@ FactorInteger[ # ] == 14 &] - Vladimir Orlovsky, Apr 23 2008
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PROG
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(PARI) k=14; start=2^k; finish=240000; v=[] for(n=start, finish, if(bigomega(n)==k, v=concat(v, n))); v
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CROSSREFS
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Cf. A101637, A101638, A101605, A101606.
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), this sequence(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: A069389 A069415 A212936 * A216074 A220767 A115348
Adjacent sequences: A069272 A069273 A069274 * A069276 A069277 A069278
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KEYWORD
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nonn
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AUTHOR
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Rick L. Shepherd, Mar 13 2002
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STATUS
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approved
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