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.

4, 6, 9, 12, 14, 18, 21, 25, 30, 33, 38, 42, 46, 49, 55, 60, 62, 69, 72, 74, 82, 85, 91, 98, 102, 106, 108, 111, 121, 129, 133, 138, 141, 150, 155, 158, 166, 169, 177, 180, 183, 192, 194, 198, 201, 213, 226, 228, 230, 235, 240, 247, 253, 259, 265, 270, 274, 278

Offset

2,1

Links

Harvey P. Dale, Table of n, a(n) for n = 2..1000

Mathematica

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 *)

Prog

(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", "))

Crossrefs

Cf. A076082.

Sequence in context: A060644 A122550 A191407 * A094202 A310666 A304231

Adjacent sequences: A076080 A076081 A076082 * A076084 A076085 A076086

Keyword

nonn

Author

Amarnath Murthy, Oct 07 2002

Extensions

More terms from Ralf Stephan, Mar 23 2003

Status

approved