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%I #12 Aug 23 2018 02:12:50
%S 561,645,1105,1729,1905,2465,2821,4371,6601,8481,8911,10585,11305,
%T 12801,13741,13981,15841,16705,18705,23001,25761,29341,30121,30889,
%U 33153,34945,39865,41041,41665,46657,52633,55245,57421,62745,63973,68101,72885,74665,75361
%N Sarrus numbers with more than 2 distinct prime factors.
%H Giovanni Resta, <a href="/A080747/b080747.txt">Table of n, a(n) for n = 1..10000</a>
%p for n from 1 to 60000 do if not isprime(n) and modp(2^(n-1),n)=1 and nops(ifactors(n)[2])>2 then printf("%d, ",n) fi od: # C. Ronaldo
%t Select[Range[76000], PowerMod[2, #-1, #] == 1 && PrimeNu[#] > 2 &] (* _Giovanni Resta_, Aug 20 2018 *)
%Y Cf. A001567.
%K nonn
%O 1,1
%A _Benoit Cloitre_, Mar 08 2003
%E Edited by C. Ronaldo (aga_new_ac(AT)hotmail.com), Dec 19 2004
%E More terms from _Giovanni Resta_, Aug 20 2018