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A286612
Numbers n for which A019565(n) <= A087207(n) < n.
4
65, 513, 1026, 4107, 8200, 8256, 16400, 16450, 16512, 16544, 16641, 32800, 32900, 33024, 33282, 33920, 49184, 65600, 65800, 66048, 66080, 131200, 131334, 132096, 132160, 163968, 262400, 262668, 264192, 264320, 274432, 327936, 524342, 524610, 524800, 524832, 525826, 528384, 532500, 540736, 548864, 655872, 786467, 1048617
OFFSET
1,1
COMMENTS
Any 2-cycle of A087207 and also any 2-cycle of A019565 (in which case A019565(x) = A087207(x) for both members of the cycle), if such cycles exist at all, must have the larger one of its members included in this sequence.
PROG
(Scheme, with Antti Karttunen's IntSeq-library)
(define A286612 (MATCHING-POS 1 1 (lambda (n) (and (< (A087207 n) n) (<= (A019565 n) (A087207 n))))))
CROSSREFS
Intersection of A286608 and A286611.
Subsequence of A285315.
Sequence in context: A251158 A251151 A222588 * A276963 A338413 A211404
KEYWORD
nonn,base
AUTHOR
Antti Karttunen, Jun 20 2017
STATUS
approved