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A355139 The indices where A355061(n) = 6.

%I A355139 #8 Jun 21 2022 10:28:12
%S A355139 3,7,11,19,46,75,113,138,169,186,227,240,287,374,382,481,528,536,672,
%T A355139 713,722,760,836,922,972,1015,1031,1052,1077,1122,1144,1235,1244,1371,
%U A355139 1392,1466,1549,1613,1669,1859,1938,2059,2109,2118,2127,2391,2557,2661,2730,2739,2765,2798,2949,2962
%N A355139 The indices where A355061(n) = 6.
%C A355139 See A355061 for further details.
%o A355139 (Python)
%o A355139 from sympy import primefactors
%o A355139 from itertools import count, islice
%o A355139 def agen(): # generator of terms
%o A355139     an1, an, f1, f, pset = 2, 6, {2}, {2, 3}, {2, 12}
%o A355139     for n in count(4):
%o A355139         if an == 6: yield n-1
%o A355139         an2, an1, an, f2, f1 = an1, an, 6, f1, f
%o A355139         f = set(primefactors(an))
%o A355139         while an*an1 in pset or f1&f == set() or f2&f != set() or f <= f1:
%o A355139             an += 1; f = set(primefactors(an))
%o A355139         pset.add(an*an1)
%o A355139 print(list(islice(agen(), 54))) # _Michael S. Branicky_, Jun 20 2022
%Y A355139 Cf. A355061, A355138.
%K A355139 nonn
%O A355139 1,1
%A A355139 _Scott R. Shannon_, Jun 20 2022