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 A354161 Index of A354160(n) in A090252. 4
 15, 29, 47, 59, 63, 65, 121, 131, 193, 239, 241, 243, 255, 257, 265, 387, 479, 483, 487, 489, 515, 527, 529, 531, 767, 775, 777, 959, 961, 967, 969, 977, 979, 1023, 1031, 1055, 1059, 1063, 1143, 1551, 1553, 1555, 1921, 1923, 1935, 1937, 1939, 1951, 1953, 1955, 1959, 1961, 2047, 2063, 2064, 2111, 2113, 2119, 2127, 2288, 3071, 3073, 3105, 3107 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Michael De Vlieger, Table of n, a(n) for n = 1..2517 PROG (Python) from itertools import count, islice from collections import deque from math import gcd, lcm from sympy import factorint def A354161_gen(): # generator of terms aset, aqueue, c, b, f, i = {1}, deque([1]), 2, 1, True, 1 while True: for m in count(c): if m not in aset and gcd(m, b) == 1: i += 1 if len(fm := factorint(m)) == sum(fm.values()) == 2: yield i aset.add(m) aqueue.append(m) if f: aqueue.popleft() b = lcm(*aqueue) f = not f while c in aset: c += 1 break A354161_list = list(islice(A354161_gen(), 25)) # Chai Wah Wu, May 31 2022 CROSSREFS Cf. A090252, A354159, A354160, A354162, A354163. Sequence in context: A001356 A104811 A131877 * A211324 A354163 A146427 Adjacent sequences: A354158 A354159 A354160 * A354162 A354163 A354164 KEYWORD nonn AUTHOR N. J. A. Sloane, May 30 2022 STATUS approved

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Last modified November 28 15:31 EST 2023. Contains 367419 sequences. (Running on oeis4.)