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 A140642 Triangle of sorted absolute values of Jacobsthal successive differences. 3
 1, 2, 3, 4, 5, 6, 8, 10, 11, 12, 16, 20, 21, 22, 24, 32, 40, 42, 43, 44, 48, 64, 80, 84, 85, 86, 88, 96, 128, 160, 168, 170, 171, 172, 176, 192, 256, 320, 336, 340, 341, 342, 344, 352, 384 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS The triangle is generated from the set of Jacobsthal numbers A001045 and all the iterated differences (see A078008, A084247), taking the absolute values and sorting into natural order. The first differences generated individually along any row of this triangle here are all in A000079. LINKS FORMULA Row sums: A113861(n+2). EXAMPLE The triangle starts .1; .2,.3; .4,.5,.6; .8,10,11,12; 16,20,21,22,24; The Jacobsthal sequence and its differences in successive rows starts: ..0,..1,..1,..3,..5,.11,.21,.43,.85,.. ..1,..0,..2,..2,..6,.10,.22,.42,.86,.. .-1,..2,..0,..4,..4,.12,.20,.44,.84,.. ..3,.-2,..4,..0,..8,..8,.24,.40,.88,.. .-5,..6,.-4,..8,..0,.16,.16,.48,.80,.. .11,-10,.12,.-8,.16,..0,.32,.32,.96,.. -21,.22,-20,.24,-16,.32,..0,.64,.64,.. .43,-42,.44,-40,.48,-32,.64,..0,128,.. The values of +-7, +-9, +-13, for example, are missing there, so 7, 9 and 13 are not in the triangle. MATHEMATICA maxTerm = 384; FixedPoint[(nMax++; Print["nMax = ", nMax]; jj = Table[(2^n - (-1)^n)/3, {n, 0, nMax}]; Table[Differences[jj, n], {n, 0, nMax}] // Flatten // Abs // Union // Select[#, 0 < # <= maxTerm &] &) &, nMax = 5 ] (* Jean-François Alcover, Dec 16 2014 *) CROSSREFS Cf. A003945. Sequence in context: A067936 A087721 A226244 * A188936 A260317 A072666 Adjacent sequences:  A140639 A140640 A140641 * A140643 A140644 A140645 KEYWORD nonn,tabl AUTHOR Paul Curtz, Jul 08 2008 EXTENSIONS Edited by R. J. Mathar, Dec 05 2008 STATUS approved

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Last modified September 25 22:18 EDT 2021. Contains 347664 sequences. (Running on oeis4.)