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Numbers n such that A036459(n) is even.
8

%I #20 Sep 03 2015 10:29:20

%S 1,2,4,9,12,16,18,20,24,25,28,30,32,40,42,44,45,48,49,50,52,54,56,63,

%T 64,66,68,70,75,76,78,80,81,88,92,98,99,102,104,105,110,112,114,116,

%U 117,121,124,128,130,135,136,138,144,147,148,152,153,154,162,164,165,169,170

%N Numbers n such that A036459(n) is even.

%C The sequence is also given by taking the smallest positive integer n such that A000005(n) is not already in the sequence. - _Drake Thomas_, May 05 2015

%H Robert Israel, <a href="/A182859/b182859.txt">Table of n, a(n) for n = 1..10000</a>

%p A036459:= proc(n) option remember;

%p procname(numtheory:-tau(n))+1;

%p end proc:

%p A036459(1):= 0: A036459(2):= 0:

%p select(t -> A036459(t)::even, [$1..1000]); # _Robert Israel_, Aug 31 2015

%t Position[Table[Length[FixedPointList[DivisorSigma[0, #] &, n]] - 2, {n, 170}], _Integer?EvenQ] // Flatten (* _Michael De Vlieger_, Aug 31 2015, after _Robert G. Wilson v_ at A036459 *)

%Y Complement of A080218.

%K nonn

%O 1,2

%A _Matthew Vandermast_, Jan 05 2011