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 A006073 Numbers n such that n, n+1 and n+2 all have same number of distinct prime divisors. 14
 2, 3, 7, 20, 33, 34, 38, 44, 50, 54, 55, 56, 74, 75, 85, 86, 91, 92, 93, 94, 98, 115, 116, 117, 122, 133, 134, 141, 142, 143, 144, 145, 146, 158, 159, 160, 175, 176, 183, 187, 200, 201, 205, 206, 207, 212, 213, 214, 215, 216, 217, 224, 235, 247 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Distinct prime divisors means that the prime divisors are counted without multiplicity. - Harvey P. Dale, Apr 19 2011 LINKS Harvey P. Dale, Table of n, a(n) for n = 1..10000 MATHEMATICA pdQ[n_]:=PrimeNu[n]==PrimeNu[n+1]==PrimeNu[n+2]; Select[Range[250], pdQ] (* Harvey P. Dale, Apr 19 2011 *) Take[Transpose[Flatten[Select[Partition[{#, PrimeNu[#]}&/@Range[250000], 3, 1], #[[1, 2]]==#[[2, 2]]==#[[3, 2]]&], 1]][[1]], {1, -1, 3}] (* Harvey P. Dale, Dec 09 2011 *) Flatten[Position[Partition[PrimeNu[Range[250]], 3, 1], _?(#[[1]]==#[[2]]== #[[3]]&), {1}, Heads->False]] (* Harvey P. Dale, Oct 30 2013 *) CROSSREFS Cf. A006049, A045932. Sequence in context: A172976 A171655 A293683 * A052402 A300041 A222939 Adjacent sequences:  A006070 A006071 A006072 * A006074 A006075 A006076 KEYWORD nonn AUTHOR STATUS approved

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Last modified August 11 00:32 EDT 2020. Contains 336403 sequences. (Running on oeis4.)