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 A138587 The union of all entries of A024495, A131708 and A024493 sorted into natural order. 2
 0, 1, 2, 3, 5, 6, 10, 11, 21, 22, 42, 43, 85, 86, 170, 171, 341, 342, 682, 683, 1365, 1366, 2730, 2731, 5461, 5462, 10922, 10923, 21845, 21846, 43690, 43691, 87381, 87382, 174762, 174763, 349525, 349526, 699050, 699051, 1398101, 1398102, 2796202, 2796203, 5592405 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS The three sequences of the definition share the same special recurrence which reflects that each equals its own sequence of third differences. LINKS G. C. Greubel, Table of n, a(n) for n = 0..1000 FORMULA a(n+8) == a(n) (mod 10), n > 1. a(2*n+1) - a(2*n) = 1. a(2*n) = A000975(n+1), n>0 (bisection). From R. J. Mathar, Nov 22 2009: (Start) a(n) = -a(n-1) +a(n-2) +a(n-3) +2*a(n-4) +2*a(n-5), n>6. G.f.: x*(3*x+4*x^2+5*x^3+4*x^4+2*x^5+1)/((1+x)*(1-2*x^2)*(1+x^2)). (End) MATHEMATICA CoefficientList[Series[x*(3*x + 4*x^2 + 5*x^3 + 4*x^4 + 2*x^5 + 1)/((1 + x)*(1 - 2*x^2)*(1 + x^2)), {x, 0, 50}], x] (* G. C. Greubel, Oct 03 2017 *) PROG (PARI) x='x+O('x^50); concat(0, Vec(x*(3*x+4*x^2+5*x^3+4*x^4 +2*x^5+ 1)/((1+x)*(1-2*x^2)*(1+x^2)))) \\ G. C. Greubel, Oct 03 2017 CROSSREFS Sequence in context: A302600 A053436 A057546 * A099350 A191173 A240026 Adjacent sequences:  A138584 A138585 A138586 * A138588 A138589 A138590 KEYWORD nonn AUTHOR Paul Curtz, May 13 2008 EXTENSIONS Edited and extended by R. J. Mathar, Nov 22 2009 STATUS approved

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Last modified January 15 18:44 EST 2019. Contains 319163 sequences. (Running on oeis4.)