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%I #14 Mar 20 2016 12:55:10
%S 4,5,7,10,12,14,15,16,17,19,21,29,30,34,36,38,40,41,42,43,44,45,48,51,
%T 52,53,55,56,57,58,61,63,64,65,67,73,77,79,82,86,87,90,91,92,100,101,
%U 102,103,106,108,110,113,114,115,120,122,123,124,125,126,127,129,130,132,134,135,136,137,140,144,146,148,149
%N Numbers n such that n and A048673(n) are of opposite parity.
%C Union of even terms of A246261 and odd terms of A246263.
%H Antti Karttunen, <a href="/A269861/b269861.txt">Table of n, a(n) for n = 1..10000</a>
%F Other identities. For all n >= 1:
%F A269862(a(n)) = n.
%t f[n_] := (Times @@ Power[If[# == 1, 1, NextPrime@ #] & /@ First@ #, Last@ #] + 1)/2 &@ Transpose@ FactorInteger@ n; Select[Range@ 150, Xor[EvenQ@ f@ #, EvenQ@ #] &] (* _Michael De Vlieger_, Mar 17 2016 *)
%o (Scheme, with _Antti Karttunen_'s IntSeq-library)
%o (define A269861 (NONZERO-POS 1 1 (lambda (n) (- (A000035 n) (A000035 (A048673 n))))))
%Y Complement: A269860.
%Y Left inverse: A269862.
%Y Cf. A000035, A048673, A246261, A246263.
%Y Cf. also A270431.
%K nonn
%O 1,1
%A _Antti Karttunen_, Mar 16 2016
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