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 A180251 Decimal expansion of 6*(phi+1)/5, where phi is (1 + sqrt(5))/2. 1
 3, 1, 4, 1, 6, 4, 0, 7, 8, 6, 4, 9, 9, 8, 7, 3, 8, 1, 7, 8, 4, 5, 5, 0, 4, 2, 0, 1, 2, 3, 8, 7, 6, 5, 7, 4, 1, 2, 6, 4, 3, 7, 1, 0, 1, 5, 7, 6, 6, 9, 1, 5, 4, 3, 4, 5, 6, 2, 5, 3, 8, 3, 4, 7, 2, 4, 6, 3, 1, 2, 5, 5, 5, 3, 8, 2, 6, 8, 2, 9, 3, 9, 6, 4, 8, 6, 4, 8, 6, 4, 5, 0, 2, 7, 2, 6, 9, 3, 6, 4, 9, 8, 1, 7, 0, 4, 9, 0, 5, 6, 9, 0, 4, 6 (list; constant; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS This is an approximation to Pi. 6*(phi+1)/5 is not equal to Pi, although some have claimed this (see Dudley). - Kellen Myers, Oct 04 2013 REFERENCES Underwood Dudley, Mathematical Cranks, MAA 1992, pp. 247, 292. Alfred S. Posamentier and Ingmar Lehmann, The (Fabulous) Fibonacci Numbers, New York, Prometheus Books, 2007, p. 119. LINKS G. C. Greubel, Table of n, a(n) for n = 1..10000 Hung Viet Chu, Square the Circle in One Minute, arXiv:1908.01202 [math.GM], 2019. Futility Closet, A Surprise Visitor FORMULA Limit of A022089(n+2)/A022088(n) as n approaches infinity. 6*(phi + 1)/5 = 6*phi^2/5 = 3(3 + sqrt(5))/5 = 9/5 + sqrt(9/5). - Charles R Greathouse IV, Sep 13 2013 Equals 24/(5-sqrt(5))^2. - Joost Gielen, Sep 20 2013 EXAMPLE 3.141640786499873817845504201238765741264371015766915434562538347246312555382... MATHEMATICA RealDigits[(6/5)GoldenRatio^2, 10, 100][[1]] (* Alonso del Arte, Apr 09 2012 *) PROG (PARI) 3*(3+sqrt(5))/5 \\ Charles R Greathouse IV, Sep 13 2013 (Magma)(3/10)*(1 + Sqrt(5))^2 // G. C. Greubel, Jan 17 2018 CROSSREFS Cf. A022088, A022089, A001622, A000796. Sequence in context: A069264 A347459 A064575 * A094119 A210622 A335113 Adjacent sequences: A180248 A180249 A180250 * A180252 A180253 A180254 KEYWORD nonn,cons AUTHOR Grant Garcia, Jan 16 2011 STATUS approved

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Last modified December 5 12:01 EST 2022. Contains 358586 sequences. (Running on oeis4.)