A321495 - OEIS

A321495

Numbers k such that k and k+1 have at least 5 but not both exactly 5 distinct prime factors.

728364, 1565564, 1774409, 1817529, 1923635, 2162094, 2187185, 2199834, 2225894, 2369850, 2557190, 2594514, 2659734, 2671305, 2794154, 2944689, 2964884, 3126045, 3139730, 3170244, 3244955, 3273809, 3279639, 3382379, 3387054, 3506810, 3555110, 3585945, 3686969, 3711630

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OFFSET

1,1

COMMENTS

Complement of A140079 (k and k+1 have exactly 5 distinct prime factors) in A321505 (k and k+1 have at least 5 distinct prime factors).

LINKS

Table of n, a(n) for n=1..30.

FORMULA

A321505 \ A140079.

MATHEMATICA

aQ[n_]:=Module[{v={PrimeNu[n], PrimeNu[n+1]}}, Min[v]>4 && v!={5, 5}]; Select[Range[120000], aQ] (* Amiram Eldar, Nov 12 2018 *)

PROG