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 A229790 Cube roots of difference of consecutive cubes, rounded. 0
 1, 2, 3, 3, 4, 4, 5, 6, 6, 6, 7, 7, 8, 8, 9, 9, 9, 10, 10, 10, 11, 11, 11, 12, 12, 12, 13, 13, 13, 14, 14, 14, 15, 15, 15, 16, 16, 16, 16, 17, 17, 17, 18, 18, 18, 18, 19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 22, 22, 22, 22, 23, 23, 23, 23, 24, 24, 24, 24 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS Table of n, a(n) for n=0..69. EXAMPLE 3n^2+3n+1 is the difference of two adjacent cubes, taking the cube root and rounding to a whole number yields an element of the series. 3 cubes is 27, inserting 3 into the formula = 37, 37 plus 27 is 64 the next cube after 27; the cube root of 37 is 3.33222... rounded to 3 is the element in the series. MATHEMATICA Table[Round[(3*n^2 + 3*n + 1)^(1/3)], {n, 0, 100}] (* T. D. Noe, Oct 22 2013 *) Round[Surd[#, 3]]&/@Differences[Range[0, 70]^3] (* Harvey P. Dale, Aug 01 2020 *) PROG (PARI) a(n)=round((3*n*(n+1)+1)^(1/3)) \\ Charles R Greathouse IV, Oct 22 2013 CROSSREFS Cf. A003215. Sequence in context: A280026 A323080 A194806 * A156261 A071823 A219642 Adjacent sequences: A229787 A229788 A229789 * A229791 A229792 A229793 KEYWORD nonn,easy AUTHOR Edmund Algeo, Oct 07 2013 STATUS approved

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Last modified June 4 13:02 EDT 2023. Contains 363128 sequences. (Running on oeis4.)