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%I #16 Dec 23 2015 14:11:40
%S 1,3,5,6,7,8,9,11,13,14,17,18,19,20,22,23,24,25,27,29,31,32,34,35,37,
%T 38,40,41,43,44,46,47,49,50,51,53,56,57,58,59,61,62,65,67,68,71,72,73,
%U 74,77,79,81,82,83,84,86,87,88,89,92,93,94,95,96,97,98,99,101,102,103,104,105,106,107,109,113,114,116,118,119,120,121,123,125,127,128
%N Least siblings in A263267-tree: numbers n for which there doesn't exist any k < n such that k - d(k) = n - d(n), where d(n) = A000005(n), the number of divisors of n.
%C Sequence A082284 sorted into ascending order, with zeros removed.
%C At least initially, most of the odd squares (A016754) seem to be in A266114, while most of the even squares (A016742) seem to be in A266115. The first exceptions to this are 63^2 = 3969 = A266115(1296), and 20^2 = 400 = A266114(269).
%H Antti Karttunen, <a href="/A266114/b266114.txt">Table of n, a(n) for n = 1..10000</a>
%F Other identities. For all n >= 1:
%F A266113(a(n)) = n.
%e 3 is present, as 3 - A000005(3) = 1, but there are no any number k less than 3 for which k - A000005(k) = 1. (Although there is a larger sibling 4, for which 4 - A000005(4) = 1 also). Thus 3 is a smallest children of 1 in a tree A263267 defined by edge-relation child - A000005(child) = parent.
%o (Scheme, with _Antti Karttunen_'s IntSeq-library)
%o (define A266114 (NONZERO-POS 1 1 A266112))
%Y Cf. A000005, A082284, A263267.
%Y Cf. A266112 (characteristic function).
%Y Cf. A266113 (least monotonic left inverse).
%Y Cf. A266115 (complement).
%Y Cf. A065091, A261089, A264988, A262509 (subsequences).
%Y Cf. also A016742, A016754.
%K nonn
%O 1,2
%A _Antti Karttunen_, Dec 21 2015