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A355139
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The indices where A355061(n) = 6.
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2
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3, 7, 11, 19, 46, 75, 113, 138, 169, 186, 227, 240, 287, 374, 382, 481, 528, 536, 672, 713, 722, 760, 836, 922, 972, 1015, 1031, 1052, 1077, 1122, 1144, 1235, 1244, 1371, 1392, 1466, 1549, 1613, 1669, 1859, 1938, 2059, 2109, 2118, 2127, 2391, 2557, 2661, 2730, 2739, 2765, 2798, 2949, 2962
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OFFSET
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1,1
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COMMENTS
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LINKS
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PROG
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(Python)
from sympy import primefactors
from itertools import count, islice
def agen(): # generator of terms
an1, an, f1, f, pset = 2, 6, {2}, {2, 3}, {2, 12}
for n in count(4):
if an == 6: yield n-1
an2, an1, an, f2, f1 = an1, an, 6, f1, f
f = set(primefactors(an))
while an*an1 in pset or f1&f == set() or f2&f != set() or f <= f1:
an += 1; f = set(primefactors(an))
pset.add(an*an1)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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