

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
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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

Table of n, a(n) for n=1..15.
G. Bannay, LE COMPTE EST BON
Joe Crump, The Nine 9s
Index entries for similar sequences


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



