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A076083 Consider all composite numbers between prime(n) and prime(n+1); take those with smallest number of divisors; a(n) is the smallest of them. 3

%I #6 Jul 06 2014 18:08:45

%S 4,6,9,12,14,18,21,25,30,33,38,42,46,49,55,60,62,69,72,74,82,85,91,98,

%T 102,106,108,111,121,129,133,138,141,150,155,158,166,169,177,180,183,

%U 192,194,198,201,213,226,228,230,235,240,247,253,259,265,270,274,278

%N Consider all composite numbers between prime(n) and prime(n+1); take those with smallest number of divisors; a(n) is the smallest of them.

%H Harvey P. Dale, <a href="/A076083/b076083.txt">Table of n, a(n) for n = 2..1000</a>

%t snd[lst_]:=First[SortBy[lst,DivisorSigma[0,#]&]]; snd/@(Range[#[[1]]+1, #[[2]]- 1]&/@Partition[Prime[Range[2,60]],2,1]) (* _Harvey P. Dale_, Jul 06 2014 *)

%o (PARI) for(n=2,100,m=99999:r=0:for(k=prime(n)+1, prime(n+1)-1,if(!isprime(k),if(numdiv(k)<m,r=k:m=numdiv(k)))):print1(r","))

%Y Cf. A076082.

%K nonn

%O 2,1

%A _Amarnath Murthy_, Oct 07 2002

%E More terms from _Ralf Stephan_, Mar 23 2003

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Last modified April 19 21:09 EDT 2024. Contains 371798 sequences. (Running on oeis4.)