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A147771
a(n) = round(n^(n/2)).
3
1, 2, 5, 16, 56, 216, 907, 4096, 19683, 100000, 534146, 2985984, 17403307, 105413504, 661735514, 4294967296, 28761784748, 198359290368, 1406563064942, 10240000000000, 76436817165460, 584318301411328, 4569515072723572
OFFSET
1,2
LINKS
MATHEMATICA
lst={}; Do[AppendTo[lst, Round[(n^n)^(1/2)]], {n, 40}]; lst
Table[Round[n^(n/2)], {n, 30}] (* Harvey P. Dale, Feb 17 2020 *)
PROG
(Python)
from gmpy2 import isqrt_rem
def A147771(n):
i, j = isqrt_rem(n**n)
return int(i+int(4*(j-i) >= 1)) # Chai Wah Wu, Aug 16 2016
CROSSREFS
Sequence in context: A149976 A141201 A149977 * A052891 A352905 A052815
KEYWORD
nonn
AUTHOR
STATUS
approved