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A018068
Powers of fourth root of 8 rounded up.
1
1, 2, 3, 5, 8, 14, 23, 39, 64, 108, 182, 305, 512, 862, 1449, 2436, 4096, 6889, 11586, 19484, 32768, 55109, 92682, 155872, 262144, 440872, 741456, 1246975, 2097152, 3526976, 5931642, 9975793, 16777216
OFFSET
0,2
LINKS
FORMULA
a(n) = ceiling(8^(n/4)). - Michel Marcus, Dec 28 2020
MAPLE
seq(ceil(8^(n/4)), n=0..40); # Robert Israel, Dec 28 2020
PROG
(PARI) a(n) = n*=3; if(n%2, sqrtnint(1<<n, 4)+1, n%4, sqrtint(1<<(n/2))+1, 1<<(n/4)); \\ Kevin Ryde, Dec 29 2020
CROSSREFS
Cf. A001018 (powers of 8).
Sequence in context: A094926 A225391 A078843 * A120400 A217283 A000621
KEYWORD
nonn
AUTHOR
STATUS
approved