|
|
A039700
|
|
Numbers k such that the largest power of 3 dividing k equals 3^omega(k).
|
|
2
|
|
|
1, 3, 18, 36, 45, 63, 72, 99, 117, 144, 153, 171, 207, 225, 261, 270, 279, 288, 333, 369, 378, 387, 423, 441, 477, 531, 540, 549, 576, 594, 603, 639, 657, 702, 711, 747, 756, 801, 873, 909, 918, 927, 945, 963, 981, 1017, 1026, 1080, 1089, 1125, 1143, 1152
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
COMMENTS
|
Here, "omega(k)" means the number of prime factors of k counted without multiplicity. - Harvey P. Dale, Sep 30 2015
|
|
LINKS
|
|
|
EXAMPLE
|
omega(18)=2 and 9=3^2 is the largest power of 3 dividing 18, hence 18 is in the sequence.
|
|
MATHEMATICA
|
Select[Range[1200], IntegerExponent[#, 3]==PrimeNu[#]&] (* Harvey P. Dale, Sep 30 2015 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|