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A119850 Positions where A119842 is greater than one. 3
36, 48, 72, 80, 100, 108, 112, 120, 144, 162, 168, 176, 180, 192, 196, 200, 208, 225, 252, 264, 270, 272, 280, 288, 300, 304, 312, 320, 324, 368, 378, 392, 396, 400, 405, 408, 420, 432, 440, 441, 448, 450, 456, 464, 468, 480, 484, 496, 500, 520, 552, 567 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
MATHEMATICA
b[s_, t_] := b[s, t] = If[Length[s] < 1, 1, Sum[If[Mod[PrimeOmega[x], 2] == 1 - t && Length[Select[s, Mod[#, x] == 0 &]] == 1, b[s~Complement~{x}, 1 - t], 0], {x, s}]]; 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]], Mod[PrimeOmega[m], 2]]]; A119842 = Array[a, 1000]; A119850 = Position[A119842, n_ /; n > 1] // Flatten (* Jean-François Alcover, Mar 03 2016, after Alois P. Heinz *)
CROSSREFS
Subset of A119848.
Sequence in context: A244326 A357605 A064597 * A357606 A348274 A033701
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jun 04 2006
STATUS
approved

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Last modified April 18 06:12 EDT 2024. Contains 371769 sequences. (Running on oeis4.)