OFFSET
1,1
COMMENTS
Composite n such that n^6 is congruent to {1, 169} mod 210. All primes > 7 satisfy this condition. - Gary Detlefs, Dec 09 2012
LINKS
T. D. Noe, Table of n, a(n) for n = 1..10000
FORMULA
a(n) ~ 4.375n. - Charles R Greathouse IV, Dec 10 2012
MAPLE
for n from 1 to 1000 do if (n^6 mod 210 = 1 or n^6 mod 210 = 169) and not isprime(n) then print(n) fi od; # Gary Detlefs, Dec 09 2012
MATHEMATICA
Select[Range[1000], Not[PrimeQ[#]] && FactorInteger[#][[1, 1]] > 7 &] (* Alonso del Arte, Dec 09 2012 *)
PROG
(PARI) is(n)=gcd(210, n)==1 && !isprime(n) \\ Charles R Greathouse IV, Dec 10 2012
(GAP) Filtered([11..1000], n->(PowerMod(n, 6, 210)=1 or PowerMod(n, 6, 210)=169) and not IsPrime(n)); # Muniru A Asiru, Nov 24 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved