login
A325424
Complement of A036668: numbers not of the form 2^i*3^j*k, i + j even, (k,6) = 1.
12
2, 3, 8, 10, 12, 14, 15, 18, 21, 22, 26, 27, 32, 33, 34, 38, 39, 40, 46, 48, 50, 51, 56, 57, 58, 60, 62, 69, 70, 72, 74, 75, 82, 84, 86, 87, 88, 90, 93, 94, 98, 104, 105, 106, 108, 110, 111, 118, 122, 123, 126, 128, 129, 130, 132, 134, 135, 136, 141, 142
OFFSET
1,1
COMMENTS
These are the numbers 2x and 3x as x ranges through the numbers in A036668.
Numbers whose squarefree part is divisible by exactly one of {2, 3}. - Peter Munn, Aug 24 2020
The asymptotic density of this sequence is 5/12. - Amiram Eldar, Sep 20 2020
LINKS
Eric Weisstein's World of Mathematics, Symmetric difference
FORMULA
(2 * {A036668}) union (3 * {A036668}). - Sean A. Irvine, May 19 2019
MATHEMATICA
a = {1}; Do[AppendTo[a, NestWhile[# + 1 &, Last[a] + 1, Apply[Or,
Map[MemberQ[a, #] &, Select[Flatten[{#/3, #/2}],
IntegerQ]]] &]], {150}]; a (* A036668 *)
Complement[Range[Last[a]], a] (* A325424 *)
(* Peter J. C. Moses, Apr 23 2019 *)
CROSSREFS
Symmetric difference of: A003159 and A007417; A036554 and A145204\{0}.
Sequence in context: A008522 A028732 A028751 * A057543 A190650 A000059
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Apr 26 2019
STATUS
approved