A225649 - OEIS

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A225649

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

2, 3, 4, 6, 10, 12, 14, 15, 16, 18, 20, 21, 22, 24, 25, 26, 28, 30, 32, 33, 34, 35, 36, 38, 39, 40, 42, 44, 45, 46, 48, 49, 50, 51, 52, 54, 55, 56, 57, 58, 60, 62, 63, 64, 65, 66, 68, 69, 70, 72, 74, 75, 76, 77, 78, 80, 81, 82, 84, 85, 86, 87, 88, 90, 91, 92

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OFFSET

1,1

COMMENTS

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

LINKS

Table of n, a(n) for n=1..66.

PROG

(Scheme with Antti Karttunen's IntSeq-library):

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

CROSSREFS

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