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A062071 a(n) = [n/1] +[n/(2^2)] + [n/(3^3)] + [n/(4^4)]+...+[n/(k^k)+..., up to infinity, where [ ] is the floor function. 1

%I

%S 1,2,3,5,6,7,8,10,11,12,13,15,16,17,18,20,21,22,23,25,26,27,28,30,31,

%T 32,34,36,37,38,39,41,42,43,44,46,47,48,49,51,52,53,54,56,57,58,59,61,

%U 62,63,64,66,67,69,70,72,73,74,75,77,78,79,80,82,83,84,85,87,88,89,90

%N a(n) = [n/1] +[n/(2^2)] + [n/(3^3)] + [n/(4^4)]+...+[n/(k^k)+..., up to infinity, where [ ] is the floor function.

%H Harry J. Smith, <a href="/A062071/b062071.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) = Sum_{i=1..n} floor(n/i^i). - _Wesley Ivan Hurt_, Sep 15 2017

%e a(7) = [7/1] + [7/4] + [7/27] + ...= 7+1+0+0... =8. a(8) = [ 8/1] + [8/4] + [8/27] + [8/256]+ ...= 8 + 2 + 0 + 0 + ... = 10.

%o (PARI) \p 10 v=[]; for(n=1,120,v=concat(v,suminf(k=1,floor(n/k^k)))); v

%o (PARI) for (n=1, 1000, write("b062071.txt", n, " ", suminf(k=1, n\k^k)\1) ) \\ _Harry J. Smith_, Jul 31 2009

%o (PARI) a(n)=sum(k=1,exp(lambertw(log(n)))+1,n\k^k) \\ _Charles R Greathouse IV_, May 28 2015

%Y Cf. A011371.

%K nonn,easy

%O 1,2

%A _Amarnath Murthy_, Jun 13 2001

%E More terms from _Jason Earls_, Jun 21 2001

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Last modified October 16 18:03 EDT 2019. Contains 328102 sequences. (Running on oeis4.)