A064846 Let r_1 = 1; r_{n+1} = [r_1; r_2, r_3,..., r_n]; n-th term is denominator of r_n.

1, 1, 1, 3, 18, 720, 1119600, 2726809311600, 16145931379144511904735600, 566327308576692897981544319968226968281922500063600

Offset

1,4

Comments

[r_1; r_2, r_3,..., r_n] is a continued fraction, where the r's are rationals. limit{n -> infinity} r_n = 1.7118691868...

Links

Table of n, a(n) for n=1..10.

Mathematica

r[1] := 1; r[n_] := r[n] = FromContinuedFraction[Table[r[i], {i, 1, n - 1, 1}]]; a[n_] := Denominator[r[n]]

Crossrefs

Cf. A053978, A064845.

Sequence in context: A365292 A070953 A163261 * A157544 A202946 A000853

Adjacent sequences: A064843 A064844 A064845 * A064847 A064848 A064849

Keyword

easy,frac,nonn

Author

Leroy Quet, Oct 31 2001; definition corrected May 04 2008

Status

approved