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 A355914 a(n) = gcd(b(n-1),b(n)), where b(n) = A351871(n). 2
 1, 2, 1, 5, 2, 1, 1, 4, 1, 1, 2, 1, 1, 2, 1, 1, 4, 1, 1, 8, 2, 3, 3, 6, 1, 1, 6, 1, 1, 6, 10, 2, 1, 1, 2, 1, 1, 2, 1, 1, 4, 2, 1, 1, 2, 30, 5, 5, 8, 1, 1, 4, 43, 1, 2, 1, 3, 4, 1, 3, 12, 1, 1, 2, 1, 1, 2, 1, 1, 2, 3, 1, 2, 1, 1, 2, 25, 1, 4, 1, 1, 6, 1, 1, 6 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,2 COMMENTS In order to understand the difference between A351871 (which cycles) and A355898 (which appears to diverge), it would be helpful to understand the difference between the respective gcd sequences (this and A355899 - the latter has a very interesting graph!). LINKS Michael S. Branicky, Table of n, a(n) for n = 2..10001 PROG (Python) from math import gcd from itertools import islice def agen(): a = [1, 2] while True: g = gcd(*a); yield g; a = [a[-1], g + sum(a)//g] print(list(islice(agen(), 85))) # Michael S. Branicky, Sep 19 2022 CROSSREFS Cf. A351871, A355898, A355899. Sequence in context: A140879 A006556 A108790 * A117941 A134566 A128694 Adjacent sequences: A355911 A355912 A355913 * A355915 A355916 A355917 KEYWORD nonn AUTHOR N. J. A. Sloane, Sep 19 2022 EXTENSIONS a(66) and beyond from Michael S. Branicky, Sep 19 2022 STATUS approved

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Last modified September 23 17:20 EDT 2023. Contains 365554 sequences. (Running on oeis4.)