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A209876
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a(n) = 36*n - 6.
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0
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30, 66, 102, 138, 174, 210, 246, 282, 318, 354, 390, 426, 462, 498, 534, 570, 606, 642, 678, 714, 750, 786, 822, 858, 894, 930, 966, 1002, 1038, 1074, 1110, 1146, 1182, 1218, 1254, 1290, 1326, 1362, 1398, 1434, 1470, 1506, 1542, 1578, 1614, 1650, 1686, 1722, 1758, 1794, 1830, 1866, 1902, 1938, 1974
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OFFSET
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1,1
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COMMENTS
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It appears that the sum of divisors of each term is a multiple of 36. For example, the divisors of a(3)=102 are {1, 2, 3, 6, 17, 34, 51, 102}, with sum 216=6*36.
It also appears that the sum of divisors of each term of {K*n-6} is a multiple of K for K = 72, 144, and 288.
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LINKS
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FORMULA
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MATHEMATICA
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36*Range[60]-6 (* or *) LinearRecurrence[{2, -1}, {30, 66}, 60] (* Harvey P. Dale, Jun 18 2021 *)
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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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