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Odd numbers in A090252 in order of appearance.
2

%I #9 May 23 2022 09:11:58

%S 1,3,5,7,9,11,13,17,19,23,25,21,29,31,37,41,43,47,53,59,61,67,71,73,

%T 55,79,27,49,83,89,97,101,103,107,109,113,127,131,137,139,149,151,157,

%U 163,167,173,179,181,191,193,197,199,211,85,121,223,227,57,229,161,233,239,241,251,257,263,269,271,277,281,283,293,307,311,313,317,331

%N Odd numbers in A090252 in order of appearance.

%H N. J. A. Sloane, <a href="/A354149/b354149.txt">Table of n, a(n) for n = 1..9988</a>

%o (Python)

%o from math import gcd, prod

%o from itertools import count, islice

%o def agen(): # generator of terms

%o alst, aset, mink = [1], {1}, 2; yield 1

%o for n in count(2):

%o k, s = mink, n - n//2

%o prodall = prod(alst[n-n//2-1:n-1])

%o while k in aset or gcd(prodall, k) != 1: k += 1

%o alst.append(k); aset.add(k)

%o if k%2 == 1: yield k

%o while mink in aset: mink += 1

%o print(list(islice(agen(), 77))) # _Michael S. Branicky_, May 23 2022

%Y Cf. A090252, A354146, A354148.

%K nonn

%O 1,2

%A _N. J. A. Sloane_, May 22 2022