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Sum of the first n numbers m such that floor(log(m)) divides m.
2

%I #15 Sep 05 2015 03:48:03

%S 3,7,12,18,25,33,43,55,69,85,103,123,144,168,195,225,258,294,333,375,

%T 420,468,519,573,629,689,753,821,893,969,1049,1133,1221,1313,1409,

%U 1509,1613,1721,1833,1949,2069,2193,2321,2453,2589,2729,2873

%N Sum of the first n numbers m such that floor(log(m)) divides m.

%H Harry J. Smith, <a href="/A066379/b066379.txt">Table of n, a(n) for n = 1..1000</a>

%p filter:= proc(n) is(n mod floor(log(n)) = 0) end proc:

%p ListTools:-PartialSums(select(filter, [$3..1000])); # _Robert Israel_, Sep 04 2015

%t Accumulate@ Select[Range[3, 200], Divisible[#, Floor@ Log@ #] &] (* _Michael De Vlieger_, Sep 04 2015 *)

%o (PARI) n=0; a=0; for (m=3, 10^9, if (m%floor(log(m)) == 0, a+=m; write("b066379.txt", n++, " ", a); if (n==1000, return))) \\ _Harry J. Smith_, Feb 12 2010

%Y Partial sums of A066378.

%K nonn

%O 1,1

%A _N. J. A. Sloane_, Dec 23 2001

%E Name corrected by _Charles R Greathouse IV_, Sep 04 2015