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%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