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A081785
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Continued cotangent for log(2).
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0
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0, 1, 5, 55, 14187, 314681540, 254841004490568887, 116515298784769863036311841843812470, 16752745298264669840183664790312981823804061660537952218518280274360024
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,3
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FORMULA
| log(2)=cot(sum(n>=0, n, (-1)^n*acot(a(n))); let b(0)=log(2), b(n)=(b(n-1)*floor(b(n-1))+1)/(b(n-1)-floor(b(n-1)) then a(n)=floor(b(n))
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PROG
| (PARI) ?bn=vector(100); b(n)=if(n<0, 0, bn[n]); bn[1]=log(2); ?for(n=2, 10, bn[n]=(b(n-1)*floor(b(n-1))+1)/(b(n-1)-floor(b(n-1)))) ?a(n)=floor(b(n+1))
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CROSSREFS
| Cf. A001620, A002666, A002667.
Sequence in context: A068666 A082780 A063855 * A144996 A129440 A045729
Adjacent sequences: A081782 A081783 A081784 * A081786 A081787 A081788
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KEYWORD
| nonn
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AUTHOR
| Benoit Cloitre (benoit7848c(AT)orange.fr), Apr 10 2003
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