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%I #37 Sep 29 2023 19:43:32
%S 0,1,16,6561,4294967296,23283064365386962890625,
%T 63340286662973277706162286946811886609896461828096,
%U 1487815647197611695910312681741273570332356717154798949898498305086387315423300999654757561928633305897036801
%N a(n) = n^(2^n).
%C Number of mappings from 2^X to X where X is an n-set.
%H Vincenzo Librandi, <a href="/A097547/b097547.txt">Table of n, a(n) for n = 0..9</a> (shortened by _N. J. A. Sloane_, Jan 13 2019)
%H Yasutoshi Kohmoto, <a href="http://boat.zero.ad.jp/~zbi74583/another02.htm">The Other Side of Mathematics</a> [broken link?]
%H Yasutoshi Kohmoto, <a href="http://web.archive.org/web/20120409075427/http://boat.zero.ad.jp/~zbi74583/another02.htm">The Other Side of Mathematics</a> [via Internet Archive Wayback-machine]
%F From _R. J. Mathar_, Apr 23 2007: (Start)
%F a(6) = A080174(6) - 1.
%F a(5) = A013737(10) = A013835(6).
%F a(4) = A000079(32) = A002489(4) = A000215(5)-1.
%F (End)
%F Sum_{n>=1} 1/a(n) = A216992. - _Amiram Eldar_, Nov 19 2020
%p a:= n-> (t-> (t@@n)(n))(j-> j^2):
%p seq(a(n), n=0..7); # _Alois P. Heinz_, Sep 29 2023
%t Table[n^2^n,{n,0,7}] (* _Vladimir Joseph Stephan Orlovsky_, Mar 01 2010 *)
%o (Magma) [n^(2^n): n in [0..12]]; // _Vincenzo Librandi_, May 25 2011
%o (PARI) a(n)=n^(1<<n) \\ _Charles R Greathouse IV_, May 25 2011
%Y Cf. A000290, A020955, A099129, A216992.
%K nonn
%O 0,3
%A _Yasutoshi Kohmoto_, Aug 28 2004