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A138702
a(n) = number of terms in the continued fraction of the absolute value of B_n, the n-th Bernoulli number.
3
1, 2, 2, 1, 2, 1, 2, 1, 2, 1, 3, 1, 6, 1, 2, 1, 7, 1, 7, 1, 4, 1, 4, 1, 6, 1, 2, 1, 6, 1, 7, 1, 7, 1, 2, 1, 10, 1, 2, 1, 8, 1, 2, 1, 3, 1, 5, 1, 10, 1, 3, 1, 7, 1, 7, 1, 6, 1, 6, 1, 17, 1, 2, 1, 7, 1, 10, 1, 2, 1, 7, 1, 23, 1, 2, 1, 2, 1, 5, 1, 18, 1, 5, 1, 16, 1, 2, 1, 10, 1, 14, 1, 6, 1, 2, 1, 18, 1, 2, 1
OFFSET
0,2
COMMENTS
The continued fraction terms being counted include the initial 0, if there is one. (a(n), for all odd n >= 3, is 1.)
LINKS
EXAMPLE
The 12th Bernoulli number is -691/2730. Now 691/2730 has the continued fraction 0 + 1/(3 + 1/(1 + 1/(19 + 1/(3 + 1/11)))), which has 6 terms (including the zero). So a(12) = 6.
PROG
(PARI)
lcf(x)=local(r); r=1; while(1, x-=floor(x); if(x==0, return(r)); x=1/x; r++)
a(n)=lcf(abs(bernfrac(n))) \\ Franklin T. Adams-Watters, May 14 2010
CROSSREFS
Sequence in context: A052005 A377902 A346707 * A344339 A348364 A279620
KEYWORD
nonn
AUTHOR
Leroy Quet, Mar 26 2008
EXTENSIONS
More terms from Franklin T. Adams-Watters, May 14 2010
STATUS
approved