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Positions of non-ones in A225650, numbers n such that n and A000793(n) have at least one common divisor > 1.
5

%I #10 May 22 2013 16:59:27

%S 2,3,4,6,10,12,14,15,16,18,20,21,22,24,25,26,28,30,32,33,34,35,36,38,

%T 39,40,42,44,45,46,48,49,50,51,52,54,55,56,57,58,60,62,63,64,65,66,68,

%U 69,70,72,74,75,76,77,78,80,81,82,84,85,86,87,88,90,91,92

%N Positions of non-ones in A225650, numbers n such that n and A000793(n) have at least one common divisor > 1.

%C Which composites are missing apart from 8, 9 and 27? See comment at A225648.

%o (Scheme with _Antti Karttunen_'s IntSeq-library):

%o (define A225649 (MATCHING-POS 1 1 (lambda (i) (> (gcd (A000793 i) i) 1))))

%Y Cf. A225648 (complement), A225651 (from n>1 onward is a subset).

%Y Cf. A225650, A225640.

%K nonn

%O 1,1

%A _Antti Karttunen_, May 13 2013