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A372824
Sequence formed as follows: for each k >= 0, insert between 3^k and 3^(k+1) the greatest power of 2 than is in the interval [3^k, 3^(k+1)], and then arrange the resulting numbers in nondecreasing order.
2
1, 2, 3, 8, 9, 16, 27, 64, 81, 128, 243, 512, 729, 2048, 2187, 4096, 6561, 16384, 19683, 32768, 59049, 131072, 177147, 524288, 531441, 1048576, 1594323, 4194304, 4782969, 8388608, 14348907, 33554432, 43046721, 67108864, 129140163, 268435456, 387420489
OFFSET
0,2
EXAMPLE
3^0 <= 2^1 < 3^1 < 2^3 < 3^2 < 2^4 < 3^3 < ...
MATHEMATICA
a[n_] := If[EvenQ[n], 3^(n/2), 2^Floor[((n + 1)/2) Log[3]/Log[2]]]
Table[a[n], {n, 0, 37}]
PROG
(PARI) a(n) = if (n%2, 3^(n\2), 2^logint(3^(n/2), 2)); \\ Michel Marcus, May 23 2024
CROSSREFS
Interspersion of A000244 and A098232.
Sequence in context: A093765 A260020 A104577 * A309017 A376191 A247375
KEYWORD
nonn
AUTHOR
Clark Kimberling, May 18 2024
STATUS
approved