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A076155 Omega(n) = Omega(n-1)^3, where Omega(m) (A001222) denotes the number of prime factors of m, counting multiplicity. 0
2, 3, 896, 960, 1344, 1944, 2160, 2496, 3240, 3264, 3600, 3648, 3712, 3744, 4416, 4536, 4736, 4860, 4928, 5568, 5600, 5616, 5952, 6000, 6240, 6624, 7290, 7344, 7392, 7616, 7808, 7872, 8160, 8208, 8352, 8400, 8512, 8736, 8928, 9024, 9120, 9936 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..42.

EXAMPLE

Omega(896) = 2^3 = Omega(895)^2, so 896 is a term of the sequence.

MATHEMATICA

Omega[n_] := Apply[Plus, Transpose[FactorInteger[n]][[2]]]; l = {2}; Do[ If[Omega[i] == (Omega[i - 1])^3, l = Append[l, i]], {i, 3, 10^4}]; l

Join[{2}, Flatten[Position[Partition[PrimeOmega[Range[10000]], 2, 1], _?(#[[1]]^3==#[[2]]&), 1, Heads->False]]+1] (* Harvey P. Dale, Sep 22 2017 *)

CROSSREFS

Sequence in context: A108332 A256115 A066685 * A136611 A004898 A062920

Adjacent sequences:  A076152 A076153 A076154 * A076156 A076157 A076158

KEYWORD

easy,nonn

AUTHOR

Joseph L. Pe, Oct 31 2002

STATUS

approved

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Last modified May 21 14:53 EDT 2019. Contains 323443 sequences. (Running on oeis4.)