A119814 Numerators of the convergents to the continued fraction for the constant A119812 defined by binary sums involving Beatty sequences: c = Sum_{n>=1} A049472(n)/2^n = Sum_{n>=1} 1/2^A001951(n).

0, 1, 6, 109, 112494, 1887350536045, 543991754934632523092182415214, 758213844806172103575972149363453352380811718063209070444420739586832237

Offset

1,3

Comments

The number of digits in these numerators are (beginning at n=2): [1,1,3,6,13,30,72,174,420,1013,2444,5901,14245,34391,83027,...].

Links

Table of n, a(n) for n=1..8.

Example

c = 0.858267656461002055792260308433375148664905190083506778667684867..
Convergents begin:
[0/1, 1/1, 6/7, 109/127, 112494/131071, 1887350536045/2199023255551,..]
where the denominators of the convergents equal [2^A001333(n-1)-1]:
[1,1,7,127,131071,2199023255551,633825300114114700748351602687,...]
and A001333 is numerators of continued fraction convergents to sqrt(2).

Prog

(PARI) {a(n)=local(M=contfracpnqn(vector(n, k, if(k==1, 0, if(k==2, 1, 4^round(((1+sqrt(2))^(k-2)+(1-sqrt(2))^(k-2))/(2*sqrt(2))) +if(k==3, 2, 2^round(((1+sqrt(2))^(k-3)-(1-sqrt(2))^(k-3))/2))))))); return(M[1, 1])}

Crossrefs

Cf. A119812 (constant), A119813 (continued fraction), A001333; A119809 (dual constant).

Sequence in context: A041149 A193810 A217987 * A227443 A050884 A156554

Adjacent sequences: A119811 A119812 A119813 * A119815 A119816 A119817

Keyword

frac,nonn

Author

Paul D. Hanna, May 26 2006

Status

approved