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a(n) = floor(n^m) where m = Sum_{k=1..n} (1/k).
2

%I #13 Dec 03 2019 14:39:33

%S 1,2,7,17,39,80,155,284,500,849,1395,2233,3487,5329,7989,11770,17068,

%T 24395,34410,47947,66063,90080,121643,162787,216013,284381,371612,

%U 482210,621605,796306,1014096,1284233,1617696,2027457,2528789,3139618

%N a(n) = floor(n^m) where m = Sum_{k=1..n} (1/k).

%H Harry J. Smith, <a href="/A067038/b067038.txt">Table of n, a(n) for n = 1..500</a>

%F a(n) = floor(n^H(n)), H = A001008/A002805. - _Alois P. Heinz_, Dec 03 2019

%e a(4) = 17 as 1 + 1/2 + 1/3 + 1/4 = 2.08333333333333... and 4^2.08333333333333... = 17.9593927729499677029365287948669...;

%e a(11) = 1395 as 1 + 1/2 + ... + 1/10 + 1/11 = 3.01987734487... and 11^3.01987734487734487734487734487734 = 1395.9767238344363983227863965103...

%o (PARI) { m=0; for (n=1, 500, m+=1/n; write("b067038.txt", n, " ", floor(n^m)) ) } \\ _Harry J. Smith_, Apr 29 2010

%Y Cf. A001008, A002805.

%K nonn

%O 1,2

%A _Amarnath Murthy_, Dec 29 2001

%E Terms added by _Harry J. Smith_, Apr 29 2010