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 A293781 First differences of A293780. 2
 3, 4, 8, 16, 16, 6, 18, 24, 12, 36, 18, 30, 24, 72, 36, 60, 48, 54, 90, 72, 120, 96, 108, 180, 144, 162, 78, 192, 216, 360, 288, 288, 120, 240, 360, 150, 90, 210, 270, 180, 300, 60, 540, 360, 240, 480, 270, 450, 90, 210, 180, 420, 540, 360, 600, 120, 1080, 450, 270 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Rémy Sigrist, Table of n, a(n) for n = 1..2260 Rémy Sigrist, Colored logarithmic scatterplot of the first 2260 terms (where the color is function of the number of distinct prime factors of A293780(n)) EXAMPLE a(1) = A293780(2) - A293780(1) = 4 - 1 = 3. MATHEMATICA Block[{s = {1}~Join~Array[Times @@ FactorInteger[#][[All, 1]] &, 10^4, 2], t}, t = 1 + Array[Count[Take[s, # - 1], s[[#]]] &, Length@ s]; Differences@ Map[FirstPosition[t, #][[1]] &, Union@ FoldList[Max, t]]] (* Michael De Vlieger, Oct 30 2017 *) PROG (PARI) lista(nn) = {nbm = 0; lastn = 0; v = vector(nn, k, factor(k)[, 1]); for (n=1, nn, vn = vector(n, k, v[k]); nbn = #select(x->(x==v[n]), vn); if (nbn > nbm, if (nbm, print1(n-lastn, ", ")); nbm = nbn; lastn = n; ); ); } \\ Michel Marcus, Oct 31 2017 CROSSREFS Cf. A055932, A293780. Sequence in context: A007486 A027977 A165438 * A202025 A227615 A049894 Adjacent sequences:  A293778 A293779 A293780 * A293782 A293783 A293784 KEYWORD nonn AUTHOR David A. Corneth, Oct 19 2017 STATUS approved

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Last modified December 14 03:31 EST 2019. Contains 329978 sequences. (Running on oeis4.)