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A018038
Powers of cube root of 21 rounded up.
21
1, 3, 8, 21, 58, 160, 441, 1217, 3357, 9261, 25551, 70492, 194481, 536559, 1480324, 4084101, 11267725, 31086799, 85766121, 236622225, 652822777, 1801088541, 4969066720, 13709278307, 37822859361, 104350401111, 287894844441, 794280046581, 2191358423330
OFFSET
0,2
LINKS
MATHEMATICA
Table[Ceiling[21^(n/3)], {n, 0, 40}] (* Vincenzo Librandi, Jan 10 2014 *)
PROG
(Magma) [Ceiling(21^(n/3)): n in [0..40]]; // Vincenzo Librandi, Jan 10 2014
CROSSREFS
Cf. powers of cube root of k ceiling up: A017981 (k=2), A017984 (k=3), A017987 (k=4), A017990 (k=5), A017993 (k=6), A017996 (k=7), A018002 (k=9), A018005 (k=10), A018008 (k=11), A018011 (k=12), A018014 (k=13), A018017 (k=14), A018020 (k=15), A018023 (k=16), A018026 (k=17), A018029 (k=18), A018032 (k=19), A018035 (k=20), this sequence (k=21), A018041 (k=22), A018044 (k=23), A018047 (k=24).
Sequence in context: A349186 A273720 A018037 * A000737 A371891 A192235
KEYWORD
nonn
EXTENSIONS
More terms from Vincenzo Librandi, Jan 10 2014
STATUS
approved