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A079890 Least number > n having one more prime factor than n, not necessarily distinct.

%I A079890 #11 Nov 21 2013 12:47:58
%S A079890 2,4,4,8,6,8,9,16,12,12,14,16,14,18,18,32,21,24,21,24,27,27,25,32,27,
%T A079890 27,36,36,33,36,33,64,42,42,42,48,38,42,42,48,46,54,46,54,54,50,49,64,
%U A079890 50,54,52,54,55,72,63,72,63,63,62,72,62,63,81,128,66,81,69,81,70,81,74,96
%N A079890 Least number > n having one more prime factor than n, not necessarily distinct.
%C A079890 A001222(a(n)) = A001222(n) + 1;
%C A079890 a(2^k) = 2^(k+1).
%C A079890 a(A076156(n)) = A076156(n)+1. - _Reinhard Zumkeller_, Feb 01 2008
%H A079890 R. Zumkeller, <a href="/A079890/b079890.txt">Table of n, a(n) for n = 1..10000</a>
%t A079890 lng[n_]:=Module[{x=n+1,pon=PrimeOmega[n]},While[PrimeOmega[x]-pon!=1, x++]; x]; Array[lng,80] (* _Harvey P. Dale_, Nov 09 2011 *)
%o A079890 (Haskell)
%o A079890 a079890 n = head [x | x <- [n + 1 ..], a001222 x == 1 + a001222 n]
%o A079890 -- _Reinhard Zumkeller_, Aug 29 2013
%Y A079890 Cf. A079891, A079892.
%Y A079890 Cf. A165712.
%K A079890 nonn,nice
%O A079890 1,1
%A A079890 _Reinhard Zumkeller_, Jan 14 2003