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A126884
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a(n) = (2^0)*(2^1)*(2^2)*(2^3)...(2^n)+1 = 2^T_n+1 (cf. A000217).
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1
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2, 3, 9, 65, 1025, 32769, 2097153, 268435457, 68719476737, 35184372088833, 36028797018963969, 73786976294838206465, 302231454903657293676545, 2475880078570760549798248449, 40564819207303340847894502572033, 1329227995784915872903807060280344577, 87112285931760246646623899502532662132737
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OFFSET
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0,1
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COMMENTS
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For n>1 every odd/even pair share at least one factor.
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LINKS
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FORMULA
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MAPLE
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a:= n-> 2^(n*(n+1)/2)+1:
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MATHEMATICA
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Table[Times@@(2^Range[0, n])+1, {n, 0, 20}] (* Harvey P. Dale, Aug 10 2021 *)
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PROG
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(PARI) a(n) = prod(k=0, n, 2^k) + 1 \\ Michel Marcus, Jul 16 2013
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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