cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A165995 a(n) = Sum_{p > n} floor(n^2/p), for primes p.

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%I A165995 #14 Dec 26 2017 18:25:32
%S A165995 0,1,2,7,9,16,19,28,40,54,60,76,81,100,121,143,151,177,184,210,241,
%T A165995 272,281,314,349,386,424,465,480,522,538,582,628,677,728,782,800,856,
%U A165995 910,970,991,1051,1072,1133,1198,1263,1285,1353,1424,1497,1571
%N A165995 a(n) = Sum_{p > n} floor(n^2/p), for primes p.
%C A165995 Also the number of integers between n and n^2 with a prime factor > n. - _Orson R. L. Peters_, Dec 04 2017
%H A165995 C. H. Gribble, <a href="/A165995/b165995.txt">Table of j, a(j) for j=1..2236</a>.
%t A165995 Block[{nn = 51, s}, s = Array[FactorInteger[#][[All, 1]] &, nn^2]; Table[Count[s[[#]] & /@ Range[n, n^2], _?(AnyTrue[#, # > n &] &)], {n, nn}]] (* _Michael De Vlieger_, Dec 04 2017 *)
%Y A165995 Cf. A165974.
%K A165995 nonn
%O A165995 1,3
%A A165995 _Christopher Hunt Gribble_, Oct 03 2009
%E A165995 Definition corrected by _Orson R. L. Peters_, Dec 04 2017