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A364576
Starting from k=1, each subsequent term is the next larger odd k such that A156552(k) < k and the ratio A156552(k)/k is nearer to 1.0 than for any previous k in the sequence.
6
1, 3, 5, 21, 323, 66297, 139965, 263375, 264845, 528581
OFFSET
1,2
COMMENTS
All the odd fixed points of map n -> A005940(n) [and its inverse, map n -> A005941(n)] are included in this sequence. This includes both the known odd fixed points, 1, 3 and 5 (see A029747), and any additional hypothetical odd composites that would satisfy the condition n == A005940(n).
This is a subsequence of A364561, so the comments given in A364564 apply also here.
EXAMPLE
k A156552(k) A156552(k)/k k-(1+A156552(k)) factorization of k
1: 0 0 0
3: 2 0.6666667 0
5: 4 0.8 0
21: 18 0.8571429 2 (3 * 7)
323: 320 0.9907121 2 (17 * 19)
66297: 65714 0.9912062 582 (3 * 7^2 * 11 * 41)
139965: 139306 0.9952917 658 (3 * 5 * 7 * 31 * 43)
263375: 262364 0.9961614 1010 (5^3 * 7^2 * 43)
264845: 264244 0.9977307 600 (5 * 7^2 * 23 * 47)
528581: 528576 0.9999905 4 (17^2 * 31 * 59).
CROSSREFS
Subsequence of A364561.
Cf. also A364551, A364564, A364572.
Sequence in context: A179265 A084253 A153889 * A186751 A280037 A292557
KEYWORD
nonn,more
AUTHOR
Antti Karttunen, Aug 06 2023
STATUS
approved