A017984 Powers of cube root of 3 rounded up.

1, 2, 3, 3, 5, 7, 9, 13, 19, 27, 39, 57, 81, 117, 169, 243, 351, 506, 729, 1052, 1517, 2187, 3155, 4550, 6561, 9463, 13648, 19683, 28388, 40943, 59049, 85164, 122827, 177147, 255491, 368481, 531441, 766471, 1105442, 1594323, 2299412, 3316326, 4782969, 6898235

Offset

0,2

Comments

Smallest integer such that a(n)^k-k^n is nonnegative for all nonnegative integers k. - Henry Bottomley, May 16 2005

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Mathematica

Table[Ceiling[3^(n/3)], {n, 0, 50}] (* Vincenzo Librandi, Jan 09 2014 *)

Prog

(Magma) [Ceiling(3^(n/3)): n in [0..50]]; // Vincenzo Librandi, Jan 09 2014
(PARI) a(n)=ceil(3^(n/3)) \\ Charles R Greathouse IV, Jan 09 2014

Crossrefs

Cf. A107586 and powers of cube root of k ceiling up: A017981 (k=2), this sequence (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), A018038 (k=21), A018041 (k=22), A018044 (k=23), A018047 (k=24).

Sequence in context: A042955 A035553 A108961 * A286330 A241378 A226275

Adjacent sequences: A017981 A017982 A017983 * A017985 A017986 A017987

Keyword

nonn

Author

N. J. A. Sloane.

Extensions

More terms from Vincenzo Librandi, Jan 09 2014

Status

approved