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A069272 11-almost primes (generalization of semiprimes). +0
11
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; listen)
OFFSET

1,1

COMMENT

Divisible by exactly 11 primes (counted with multiplicity).

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

PROGRAM

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

CROSSREFS

Cf. A001358 (semiprimes), A046314 (10-almost primes), A069273 (12-almost primes) - A069281 (20-almost primes).

Sequence in context: A065341 A135976 A035892 this_sequence A135290 A100629 A017686

Adjacent sequences: A069269 A069270 A069271 this_sequence A069273 A069274 A069275

KEYWORD

nonn

AUTHOR

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

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Last modified December 20 00:58 EST 2009. Contains 171054 sequences.


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