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The indices where A355061(n) = 6.
2

%I #8 Jun 21 2022 10:28:12

%S 3,7,11,19,46,75,113,138,169,186,227,240,287,374,382,481,528,536,672,

%T 713,722,760,836,922,972,1015,1031,1052,1077,1122,1144,1235,1244,1371,

%U 1392,1466,1549,1613,1669,1859,1938,2059,2109,2118,2127,2391,2557,2661,2730,2739,2765,2798,2949,2962

%N The indices where A355061(n) = 6.

%C See A355061 for further details.

%o (Python)

%o from sympy import primefactors

%o from itertools import count, islice

%o def agen(): # generator of terms

%o an1, an, f1, f, pset = 2, 6, {2}, {2, 3}, {2, 12}

%o for n in count(4):

%o if an == 6: yield n-1

%o an2, an1, an, f2, f1 = an1, an, 6, f1, f

%o f = set(primefactors(an))

%o while an*an1 in pset or f1&f == set() or f2&f != set() or f <= f1:

%o an += 1; f = set(primefactors(an))

%o pset.add(an*an1)

%o print(list(islice(agen(), 54))) # _Michael S. Branicky_, Jun 20 2022

%Y Cf. A355061, A355138.

%K nonn

%O 1,1

%A _Scott R. Shannon_, Jun 20 2022