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A069272
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11-almost primes (generalization of semiprimes).
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29
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2048, 3072, 4608, 5120, 6912, 7168, 7680, 10368, 10752, 11264, 11520, 12800, 13312, 15552, 16128, 16896, 17280, 17408, 17920, 19200, 19456, 19968, 23328, 23552, 24192, 25088, 25344, 25920, 26112, 26880, 28160, 28800, 29184, 29696
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OFFSET
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1,1
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COMMENTS
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Product of 11 not necessarily distinct primes.
Divisible by exactly 11 prime powers (not including 1).
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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 = 11.
a(n) ~ 3628800n log n / (log log n)^10. - Charles R Greathouse IV, May 06 2013
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MATHEMATICA
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Select[Range[9000], Plus @@ Last /@ FactorInteger[ # ] == 11 &] - Vladimir Orlovsky, Apr 23 2008
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PROG
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(PARI) k=11; start=2^k; finish=30000; 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), this sequence (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: A135976 A222526 A035892 * A220584 A195069 A135290
Adjacent sequences: A069269 A069270 A069271 * A069273 A069274 A069275
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KEYWORD
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nonn
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AUTHOR
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Rick L. Shepherd, Mar 12 2002
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STATUS
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approved
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