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A052299 Minimal number of distinct prime factors of any composite number between n-th and (n+1)-st primes. 0

%I #14 Nov 05 2021 10:07:44

%S 1,2,1,2,1,2,2,1,3,1,2,3,2,1,2,3,1,2,2,2,1,2,2,2,3,2,2,2,1,1,2,3,2,3,

%T 2,2,2,1,2,3,2,2,2,3,2,2,2,3,2,2,3,1,1,2,2,3,2,2,3,1,2,2,3,2,2,2,1,3,

%U 2,2,1,2,2,2,2,2,2,2,2,4,2,2,2,2,2,2,2,4,2,2,2,2,2,2,2,1,3,1,2,2,2,2,4,2,2

%N Minimal number of distinct prime factors of any composite number between n-th and (n+1)-st primes.

%e n=81: p(81)=419, p(82)=421. The intermediate range of composites includes only 420=4*3*5*7 having 4 prime-factors, so a(81)=4;

%t Min[PrimeNu[Range[#[[1]]+1,#[[2]]-1]]]&/@Partition[Prime[ Range[ 2,110]],2,1] (* _Harvey P. Dale_, Mar 31 2012 *)

%Y Cf. A052180, A052248.

%K nonn

%O 2,2

%A _Labos Elemer_, Feb 09 2000

%E Offset corrected by _Sean A. Irvine_, Nov 04 2021

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Last modified March 29 05:48 EDT 2024. Contains 371265 sequences. (Running on oeis4.)