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Nonprime terms in A354790 in order of appearance.
5

%I #17 Jul 18 2022 09:48:48

%S 1,6,35,22,39,85,14,33,65,34,133,69,319,155,481,82,119,57,253,1247,

%T 235,403,74,287,901,177,1159,737,1633,2117,215,611,2449,166,3293,679,

%U 697,159,1121,671,1541,2059,365,4343,1339,5029,3379,158,3071,623,1649,4633

%N Nonprime terms in A354790 in order of appearance.

%H Rémy Sigrist, <a href="/A354792/b354792.txt">Table of n, a(n) for n = 1..5715</a>

%H Rémy Sigrist, <a href="/A354792/a354792.txt">C program</a>

%o (Python)

%o from math import lcm, gcd

%o from itertools import count, islice

%o from collections import deque

%o from sympy import factorint

%o def A354792_gen(): # generator of terms

%o aset, aqueue, c, b, f = {1}, deque([1]), 2, 1, True

%o yield 1

%o while True:

%o for m in count(c):

%o if m not in aset and gcd(m,b) == 1 and all(map(lambda n:n<=1,fs:=factorint(m).values())):

%o if len(fs) > 1:

%o yield m

%o aset.add(m)

%o aqueue.append(m)

%o if f: aqueue.popleft()

%o b = lcm(*aqueue)

%o f = not f

%o while c in aset:

%o c += 1

%o break

%o A354792_list = list(islice(A354792_gen(),30)) # _Chai Wah Wu_, Jul 17 2022

%o (C) See Links section.

%Y Cf. A354790, A354791.

%K nonn

%O 1,2

%A _Michael De Vlieger_ and _N. J. A. Sloane_, Jul 17 2022

%E More terms from _Rémy Sigrist_, Jul 17 2022