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A161913 Numbers k such that A001223(k) <> A000005(k). 5

%I #9 Feb 03 2019 14:56:16

%S 4,9,10,11,12,15,16,19,20,21,23,25,26,28,29,30,31,33,34,35,36,37,39,

%T 40,42,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,

%U 66,67,68,69,70,71,72,73,74,75,77,78

%N Numbers k such that A001223(k) <> A000005(k).

%H Nathaniel Johnston, <a href="/A161913/b161913.txt">Table of n, a(n) for n = 1..10000</a>

%H Omar E. Pol, <a href="http://www.polprimos.com/imagenespub/polprdipi.jpg">Illustration: Divisors and pi(x)</a>

%p p2:=2:for n from 1 to 78 do p1:=p2:p2:=ithprime(n+1):if(p2-p1<>tau(n))then print(n);fi:od: # _Nathaniel Johnston_, Apr 15 2011

%Y Cf. A000005, A001223, A068526, A161911, A161912, A162188, A162189.

%K easy,nonn

%O 1,1

%A _Omar E. Pol_, Jul 04 2009

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Last modified April 23 07:57 EDT 2024. Contains 371905 sequences. (Running on oeis4.)