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%I #12 Oct 13 2023 11:46:25
%S 1,3,12,32,92,292,995,3029,9651,31817
%N a(n) = A365737(10^n).
%H Paul Pollack, Carl Pomerance and Enrique Treviño, <a href="https://math.dartmouth.edu/~carlp/MonotonePhi.pdf">Sets of monotonicity for Euler's totient function</a>, preprint. See M↓(n).
%H Paul Pollack, Carl Pomerance and Enrique Treviño, <a href="https://doi.org/10.1007/s11139-012-9386-6">Sets of monotonicity for Euler's totient function</a>, Ramanujan J. 30 (2013), no. 3, 379--398.
%H Terence Tao, <a href="https://arxiv.org/abs/2309.02325">Monotone non-decreasing sequences of the Euler totient function</a>, arXiv:2309.02325 [math.NT], 2023.
%o (Python)
%o from bisect import bisect
%o from sympy import totient
%o def A365738(n):
%o k = 10**n
%o plist, qlist, c = tuple(-totient(i) for i in range(1,k+1)), [0]*(k+1), 0
%o for i in range(k):
%o qlist[a:=bisect(qlist,plist[i],lo=1,hi=c+1,key=lambda x:plist[x])]=i
%o c = max(c,a)
%o return c
%Y Cf. A000010, A000720.
%Y Cf. A365398, A365399, A365400, A365474, A365737, A365740, A365741, A061070.
%K nonn,hard,more
%O 0,2
%A _Chai Wah Wu_, Sep 17 2023
%E a(9) from _Chai Wah Wu_, Oct 13 2023
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