|
| |
|
|
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
|
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 A258736 A255666
Adjacent sequences: A069272 A069273 A069274 * A069276 A069277 A069278
|
|
|
KEYWORD
|
nonn
|
|
|
AUTHOR
|
Rick L. Shepherd, Mar 13 2002
|
|
|
STATUS
|
approved
|
| |
|
|
