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 A071848 a(n) = smallest positive integer that cannot be obtained using the number n at most n times and the operations +, -, *, /, where intermediate subexpressions must be integers. 0
 2, 3, 5, 10, 13, 22, 38, 85, 138, 246, 547, 1121, 2792, 3967, 12756 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Joe Crump's page indicates that a(9) = 195 if noninteger subexpressions are permitted. - David W. Wilson, Jan 14 2007 LINKS G. Bannay, LE COMPTE EST BON Joe Crump, The Nine 9s EXAMPLE a(3)=5 because using 3 at most thrice we can have 3/3=1, 3-(3/3)=2, 3=3, 3+(3/3)=4 but we cannot obtain 5 this way. CROSSREFS Cf. A060315. Sequence in context: A084760 A186082 A103746 * A268176 A120938 A120610 Adjacent sequences:  A071845 A071846 A071847 * A071849 A071850 A071851 KEYWORD hard,more,nonn AUTHOR Koksal Karakus (karakusk(AT)hotmail.com), Jun 09 2002 EXTENSIONS Definition corrected by David W. Wilson, Jan 14 2007 Definition changed (to reflect wording of the example) by Jason Taff (jtaff(AT)jburroughs.org), Apr 07 2010 STATUS approved

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Last modified October 20 15:07 EDT 2019. Contains 328267 sequences. (Running on oeis4.)