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A105215
Minimum numerator among the n! ratios equal to the continued fractions which have the permutations of (1,2,3,...,n) for terms.
1
1, 3, 9, 37, 183, 1089, 7507, 59261, 525432, 5185027, 56276118, 667218665, 8572665529, 118743064065, 1763010417987, 27944432899993, 470820846422697, 8404897200626691, 158440099278231667, 3145660094900520781
OFFSET
1,2
COMMENTS
Calculated by Vladeta Jovovic and David W. Wilson.
LINKS
MAPLE
r:= proc(l) local j; infinity; for j to nops(l) do l[j] +1/% od end: gl:= proc(n) local u, o, l, r; u:= 1; o:= n; l:=NULL; r:=NULL; do if u>o then break fi; l:= l, u; u:= u+1; if u>o then break fi; r:= u, r; u:= u+1; if u>o then break fi; l:= l, o; o:= o-1; if u>o then break fi; r:= o, r; o:= o-1 od; [l, r] end: a:= n-> numer (r (gl (n))): seq (a(n), n=1..25); # Alois P. Heinz, Nov 18 2009
MATHEMATICA
(* Script not suitable for more than a few terms *)
a[n_] := FromContinuedFraction /@ Permutations[Range[n]] // Numerator // Min;
Array[a, 10] (* Jean-François Alcover, Nov 18 2020 *)
CROSSREFS
Cf. A105151.
Sequence in context: A006229 A321734 A008986 * A158053 A009179 A030819
KEYWORD
nonn
AUTHOR
Leroy Quet, Apr 12 2005
EXTENSIONS
More terms from Alois P. Heinz, Nov 18 2009
STATUS
approved