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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A171245 Reciprocals of the deviation of continued fraction convergents from Pi.

Original entry on oeis.org

7, -790, 12016, -3748629, 1730431227, -3015428685, 8172837003, -34313104062, 114738541304, -620832653094, 2474837590227, -45157370341559, 1726856191927439, -6094457427533473, 12791098836150787, -51642743340781227, 325724575136738920, -1813676066719263909
Offset: 1

Views

Author

Phil Carmody, Dec 06 2009

Keywords

Comments

Clearly the terms alternate in sign, but the initial choice of sign was arbitrary.

Examples

			The first convergent to Pi, 3, is just over 1/7 too low, so 7 is the first term.
The second convergent, 22/7, is 0.001264+ too high, which is just over 1/790, so -790 is the second term.
		

Crossrefs

Cf. A001203.

Programs

  • PARI
    for(x=1,10,t=contfracpnqn(contfrac(Pi,x));print(truncate(1/(Pi-t[1,1]/t[2,1]))))

Extensions

More terms from Jinyuan Wang, Aug 23 2021