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A069275 14-almost primes (generalization of semiprimes). 27
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

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

LINKS

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

Eric Weisstein's World of Mathematics, Almost Prime.

FORMULA

Product p_i^e_i with Sum e_i = 14.

MATHEMATICA

Select[Range[50000], Plus @@ Last /@ FactorInteger[ # ] == 14 &] (* Vladimir Joseph Stephan Orlovsky, Apr 23 2008 *)

PROG

(PARI) k=14; start=2^k; finish=240000; v=[] for(n=start, finish, if(bigomega(n)==k, v=concat(v, n))); v

CROSSREFS

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

KEYWORD

nonn

AUTHOR

Rick L. Shepherd, Mar 13 2002

STATUS

approved

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Last modified November 26 14:56 EST 2014. Contains 250079 sequences.