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A079372 Cost'{e} prime expansion of sqrt(2) - 1. 3
3, 5, 5, 17, 11, 3, 29, 31, 29, 13, 7, 37, 7, 5, 3, 5, 5, 5, 11, 17, 7, 13, 13, 17, 11, 5, 3, 31, 31, 53, 41, 97, 47, 19, 17, 17, 41, 71, 29, 11, 211, 23, 79, 17, 5, 7, 23, 17, 5, 3, 11, 5, 2, 17, 7, 17, 5, 2, 23, 11, 3, 3, 5, 5, 3, 3, 5 (list; graph; refs; listen; history; internal format)
OFFSET

0,1

COMMENTS

For x in (0,1], define P(x) = min{p: p prime, 1/x < p}, Phi(x) = P(x)x - 1. Cost'{e} prime expansion of x(0) is sequence a(0), a(1), ... given by x(n) = Phi(x(n-1)) (n>0), a(n) = P(x(n)) (n >= 0).

LINKS

Nathaniel Johnston, Table of n, a(n) for n = 0..5000

A. Cost'{e} [Coste], Sur un syst`{e}me fibr'{e} li'{e} a la suite des nombres premiers, Exper. Math., 11 (2002), 383-405.

MAPLE

Digits := 200: P := proc(x) local y; y := ceil(evalf(1/x)); if isprime(y) then y else nextprime(y); fi; end; F := proc(x) local y, i, t1; y := x; t1 := []; for i from 1 to 50 do p := P(y); t1 := [op(t1), p]; y := p*y-1; od; t1; end; F(sqrt(2)-1);

CROSSREFS

Cf. A079373, A079374, A079366-A079368.

Sequence in context: A084041 A028254 A137780 * A055382 A165235 A200771

Adjacent sequences:  A079369 A079370 A079371 * A079373 A079374 A079375

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com), Feb 16 2003

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Last modified February 17 14:50 EST 2012. Contains 206050 sequences.