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A137244
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a(n) = lcm_{k=0..n} (k! + 1).
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1
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2, 2, 6, 42, 1050, 127050, 13086150, 65967282150, 2659866783570150, 13594579130827036650, 4484729304047661947505150, 179016047168539016473835519025150, 85748973198421705721932588223712809265150, 533960639770963461900374948788827304744234574385150
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OFFSET
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0,1
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COMMENTS
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I came upon this sequence in an attempt to solve an open Erdős problem: Show that Sum_{k>=0} 1/(k!+1) is rational/irrational/transcendental.
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LINKS
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FORMULA
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a(n) = lcm_{k=0..n} (k! + 1).
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MATHEMATICA
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With[{t=Range[0, 20]!+1}, Table[LCM@@Take[t, n], {n, Length[t]}]] (* Harvey P. Dale, Dec 21 2015 *)
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PROG
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(PARI) a(n) = {lc = 1; for (k=0, n, lc = lcm(lc, k!+1); ); return (lc); } \\ Michel Marcus, Jul 25 2013
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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