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%I #8 Jan 18 2023 14:24:12
%S 1,1,1,1,4,4,27,27,256,256,3125,3125,46656,46656,823543,823543,
%T 16777216,16777216,387420489,387420489,10000000000,10000000000,
%U 285311670611,285311670611,8916100448256,8916100448256,302875106592253
%N a(n) = floor(n/2)^floor(n/2).
%F a(n) = (n/2)^(n/2)(1+(-1)^n)/2+((n-1)/2)^((n-1)/2)(1-(-1)^n)/2.
%F a(2n) = a(2n+1) = n^n = A000312(n).
%o (Python)
%o def A110139(n): return (m:=n>>1)**m # _Chai Wah Wu_, Jan 18 2023
%Y Cf. A000312.
%K easy,nonn
%O 0,5
%A _Paul Barry_, Jul 13 2005