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A119840 Positions where new distinct values appear in A114717. 4

%I #9 Mar 03 2016 03:16:48

%S 1,6,12,24,30,36,60,72,96,120,144,180,192,210,216,240,288,360,384,420,

%T 432,480,576,720,768,840,864,900,960,1080,1152,1260,1296,1440,1536,

%U 1680,1728,1800,1920,2160,2304,2310,2520,2592,2880,3072,3360,3456,3600,3840,4320,4608,4620

%N Positions where new distinct values appear in A114717.

%H Alois P. Heinz, <a href="/A119840/b119840.txt">Table of n, a(n) for n = 1..69</a>

%t b[s_] := b[s] = If[Length[s] < 2, 1, Sum[If[Length[Select[s, Mod[#, x] == 0 &]] == 1, b[Complement[s, {x}]], 0], {x, s}]]; a[n_] := a[n] = Module[{l, m}, l = Sort[FactorInteger[n], #1[[2]] > #2[[2]] &]; m = Product[Prime[i ]^l[[ i]][[2]], {i, 1, Length[l]}]; b[Divisors[m][[2 ;; -2]] ]]; A119840 = Reap[For[k = 1, k < 5000, k++, ak = a[k]; If[FreeQ[Array[a, k - 1], ak], Print[k]; Sow[k]]]][[2, 1]] (* _Jean-François Alcover_, Mar 03 2016, after _Alois P. Heinz_ *)

%Y Subset of A025487. Cf. A119500, A119841.

%K nonn

%O 1,2

%A _Antti Karttunen_, May 26 2006

%E a(19)-a(53) from _Alois P. Heinz_, Aug 06 2012

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Last modified April 23 13:02 EDT 2024. Contains 371913 sequences. (Running on oeis4.)