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 A122553 a(0)=1, a(n)=3 for n > 0. 26
 1, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3 (list; constant; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Continued fraction for ((sqrt(13) - 1))/2. Decimal expansion of 4/30. - Alonso del Arte, Aug 16 2012 4/3 is the volume of the regular octahedron inscribed in the unit-radius sphere. - Amiram Eldar, Jun 02 2023 LINKS Table of n, a(n) for n=0..104. Index entries for linear recurrences with constant coefficients, signature (1). FORMULA a(n) = 3 - 2*0^n. G.f.: (1 + 2*x)/(1 - x). Sum_{n >= 0} a(n)*10^(-n) = 4/3. From Amiram Eldar, Jun 05 2021: (Start) 4/3 = Product_{k>=1} (1 + 1/2^(2^k)). 4/3 = Sum_{k>=0} binomial(2*k,k)/((k+2)*4^k). (End) MATHEMATICA RealDigits[4/3, 10, 105][[1]] (* Alonso del Arte, Aug 16 2012 *) PadRight[{1}, 120, 3] (* Harvey P. Dale, Jul 21 2023 *) PROG (PARI) a(n)=(n>=0)+2*(n>0) \\ Jaume Oliver Lafont, Mar 26 2009 CROSSREFS Cf. A118273 (cube), A339259 (regular icosahedron), A363437 (regular tetrahedron), A363438 (regular dodecahedron). Sequence in context: A010701 A290858 A174971 * A157831 A032552 A087717 Adjacent sequences: A122550 A122551 A122552 * A122554 A122555 A122556 KEYWORD nonn,cofr,easy,cons AUTHOR Philippe Deléham, Sep 20 2006 STATUS approved

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Last modified October 1 22:38 EDT 2023. Contains 365828 sequences. (Running on oeis4.)