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A222621
a(n) = (2n-1)^(2n).
3
1, 81, 15625, 5764801, 3486784401, 3138428376721, 3937376385699289, 6568408355712890625, 14063084452067724991009, 37589973457545958193355601, 122694327386105632949003612841, 480250763996501976790165756943041, 2220446049250313080847263336181640625
OFFSET
1,2
LINKS
FORMULA
a(n) = A005408(n-1)^A005843(n). - Michel Marcus, Apr 14 2018
Sum_{n>=1} 1/a(n) = A338168. - Amiram Eldar, Nov 29 2020
EXAMPLE
1^2; 3^4; 5^6; 7^8 and so on.
MATHEMATICA
Table[(2 n - 1)^(2 n), {n, 20}] (* T. D. Noe, Feb 26 2013 *)
PROG
(Magma) [(2*n - 1)^(2*n): n in [1..13]]; // Vincenzo Librandi, Feb 26 2013
(PARI) a(n)=(2*n-1)^(2*n) \\ Charles R Greathouse IV, Aug 20 2013
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Dave Durgin, Feb 26 2013
STATUS
approved