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A059921
a(n) = floor(n^((n+1)/n)).
6
1, 2, 4, 5, 6, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75
OFFSET
1,2
COMMENTS
Infinitely many integers are missing, starting 3, 7, 18, 50, 140; their ratios tend to e. - Charles R Greathouse IV, Aug 21 2011
LINKS
FORMULA
a(n) = floor(n^(1+1/n)). - M. F. Hasler, Nov 03 2014
MATHEMATICA
Table[Floor[n^((n+1)/n)], {n, 80}] (* Harvey P. Dale, Jul 22 2019 *)
PROG
(PARI) { for (n=1, 1000, write("b059921.txt", n, " ", floor(n^((n + 1)/n))); ) } \\ Harry J. Smith, Jun 30 2009
(PARI) A059921(n)=n^(1+1/n)\1 \\ M. F. Hasler, Nov 03 2014
(Python)
from sympy import integer_nthroot
def A059921(n): return integer_nthroot(n**(n+1), n)[0] # Chai Wah Wu, Sep 04 2024
CROSSREFS
Cf. A249669.
Sequence in context: A133398 A138836 A175431 * A062289 A172284 A039242
KEYWORD
easy,nonn
AUTHOR
Fabian Rothelius, Feb 09 2001
STATUS
approved