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A069275 14-almost primes (generalization of semiprimes). 29
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
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
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 A258736 A255666
KEYWORD
nonn
AUTHOR
Rick L. Shepherd, Mar 13 2002
STATUS
approved

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Last modified March 19 03:33 EDT 2024. Contains 370952 sequences. (Running on oeis4.)