OFFSET
0,3
COMMENTS
Number of mappings from 2^X to X where X is an n-set.
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..9 (shortened by N. J. A. Sloane, Jan 13 2019)
Yasutoshi Kohmoto, The Other Side of Mathematics [broken link?]
Yasutoshi Kohmoto, The Other Side of Mathematics [via Internet Archive Wayback-machine]
FORMULA
From R. J. Mathar, Apr 23 2007: (Start)
a(6) = A080174(6) - 1.
(End)
Sum_{n>=1} 1/a(n) = A216992. - Amiram Eldar, Nov 19 2020
MAPLE
a:= n-> (t-> (t@@n)(n))(j-> j^2):
seq(a(n), n=0..7); # Alois P. Heinz, Sep 29 2023
MATHEMATICA
Table[n^2^n, {n, 0, 7}] (* Vladimir Joseph Stephan Orlovsky, Mar 01 2010 *)
PROG
(Magma) [n^(2^n): n in [0..12]]; // Vincenzo Librandi, May 25 2011
(PARI) a(n)=n^(1<<n) \\ Charles R Greathouse IV, May 25 2011
CROSSREFS
KEYWORD
nonn
AUTHOR
Yasutoshi Kohmoto, Aug 28 2004
STATUS
approved