OFFSET
1,1
COMMENTS
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..200 (terms 1..100 from Harvey P. Dale)
EXAMPLE
13 is a term since 14 = 2*7, 15 = 3*5, 16 = 2^4 are the numbers between 13 and the next prime 17; 419 is a term since 420 = 2^2*3*5*7 is the only number between 419 and the next prime 421.
MATHEMATICA
lpf7Q[n_]:=Max[Flatten[Transpose[FactorInteger[#]][[1]]&/@Range[ n+1, NextPrime[ n]-1]]]==7; Select[Prime[Range[22000]], lpf7Q] (* Harvey P. Dale, Sep 25 2015 *)
PROG
(PARI) {forprime(p=2, 250000, q=nextprime(p+1); m=0; j=p+1; while(j<q&&m<=7, f=factor(j); a=f[matsize(f)[1], 1]; if(m<a, m=a); j++); if(m==7, print1(p, ", ")))}
CROSSREFS
KEYWORD
nonn
AUTHOR
Klaus Brockhaus, Feb 10 2003
STATUS
approved