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A354163 Index of A354162(n) in A090252.

%I A354163 #9 Jun 01 2022 02:01:30
%S A354163 15,29,59,63,65,121,131,193,239,241,243,255,257,265,387,479,483,487,
%T A354163 489,515,527,529,531,775,777,959,961,967,969,977,979,1023,1031,1055,
%U A354163 1059,1063,1143,1551,1553,1555,1921,1923,1935,1937,1939,1951,1953,1955,1959,1961,2047,2063,2064,2111,2113,2119,2127,2288,3073,3105,3107,3111,3113,3839
%N A354163 Index of A354162(n) in A090252.
%o A354163 (Python)
%o A354163 from itertools import count, islice
%o A354163 from collections import deque
%o A354163 from math import gcd, lcm
%o A354163 from sympy import factorint
%o A354163 def A354163_gen(): # generator of terms
%o A354163     aset, aqueue, c, b, f, i = {1}, deque([1]), 2, 1, True, 1
%o A354163     while True:
%o A354163         for m in count(c):
%o A354163             if m not in aset and gcd(m,b) == 1:
%o A354163                 i += 1
%o A354163                 if m % 2 and len(fm := factorint(m)) == sum(fm.values()) == 2:
%o A354163                     yield i
%o A354163                 aset.add(m)
%o A354163                 aqueue.append(m)
%o A354163                 if f: aqueue.popleft()
%o A354163                 b = lcm(*aqueue)
%o A354163                 f = not f
%o A354163                 while c in aset:
%o A354163                     c += 1
%o A354163                 break
%o A354163 A354163_list = list(islice(A354163_gen(),25)) # _Chai Wah Wu_, May 31 2022
%Y A354163 Cf. A090252, A354159, A354160, A354161, A354162.
%K A354163 nonn
%O A354163 1,1
%A A354163 _N. J. A. Sloane_, May 30 2022