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A036667 Numbers of the form 2^i*3^j, i+j even. 6
1, 4, 6, 9, 16, 24, 36, 54, 64, 81, 96, 144, 216, 256, 324, 384, 486, 576, 729, 864, 1024, 1296, 1536, 1944, 2304, 2916, 3456, 4096, 4374, 5184, 6144, 6561, 7776, 9216, 11664, 13824, 16384, 17496, 20736, 24576, 26244, 31104, 36864, 39366 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
FORMULA
A069352(a(n)) mod 2 = 0. - Reinhard Zumkeller, May 16 2015
Sum_{n>=1} 1/a(n) = 7/4. - Amiram Eldar, Feb 18 2021
MATHEMATICA
max = 40000;
Reap[Do[k = 2^i 3^j; If[k <= max && EvenQ[i+j], Sow[k]], {i, 0, Log[2, max] // Ceiling}, {j, 0, Log[3, max] // Ceiling}]][[2, 1]] // Union (* Jean-François Alcover, Aug 04 2018 *)
PROG
(Haskell)
a036667 n = a036667_list !! (n-1)
a036667_list = filter (even . flip mod 2 . a001222) a003586_list
-- Reinhard Zumkeller, May 16 2015
CROSSREFS
Complement of A257999 with respect to A003586.
Intersection of A028260 and A003586.
Cf. A025620 (subsequence), A069352, A022328, A022329.
Sequence in context: A189484 A155567 A225377 * A056016 A231997 A220144
KEYWORD
nonn
AUTHOR
EXTENSIONS
Offset corrected by Reinhard Zumkeller, May 16 2015
STATUS
approved

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Last modified March 28 07:33 EDT 2024. Contains 371235 sequences. (Running on oeis4.)