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A069272 11-almost primes (generalization of semiprimes). 29
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 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Product of 11 not necessarily distinct primes.

Divisible by exactly 11 prime powers (not including 1).

LINKS

D. W. Wilson, Table of n, a(n) for n = 1..10000

Eric Weisstein's World of Mathematics, Link to a section of The World of Mathematics.

FORMULA

Product p_i^e_i with Sum e_i = 11.

MATHEMATICA

Select[Range[9000], Plus @@ Last /@ FactorInteger[ # ] == 11 &] - Vladimir Orlovsky, Apr 23 2008

PROG

(PARI) k=11; start=2^k; finish=30000; v=[] for(n=start, finish, if(bigomega(n)==k, v=concat(v, n))); v

CROSSREFS

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: A065341 A135976 A035892 * A195069 A135290 A204837

Adjacent sequences:  A069269 A069270 A069271 * A069273 A069274 A069275

KEYWORD

nonn

AUTHOR

Rick L. Shepherd (rshepherd2(AT)hotmail.com), Mar 12 2002

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Last modified February 14 09:18 EST 2012. Contains 205614 sequences.